How to find the length of the side of an equilateral triangle - ISEE Upper Level Quantitative Reasoning
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For an equilateral triangle, Side A measures 
and Side B measures 
. What is the length of Side A?
For an equilateral triangle, Side A measures
Tap to reveal answer
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for 
.
You now know that 
, but this is not your answer. The question asked for the length of Side A, so you need to plug 3 into that equation.
So the length of Side A (and Side B for that matter) is 8.
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for
You now know that
So the length of Side A (and Side B for that matter) is 8.
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One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
Tap to reveal answer
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
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If an equilateral triangle has a perimeter of 18in, what is the length of one side?
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
Tap to reveal answer
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
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An equilateral triangle has a perimeter of 39in. Find the length of one side.
An equilateral triangle has a perimeter of 39in. Find the length of one side.
Tap to reveal answer
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
← Didn't Know|Knew It →
For an equilateral triangle, Side A measures and Side B measures . What is the length of Side A?
For an equilateral triangle, Side A measures
Tap to reveal answer
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for .
You now know that , but this is not your answer. The question asked for the length of Side A, so you need to plug 3 into that equation.
So the length of Side A (and Side B for that matter) is 8.
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for
You now know that
So the length of Side A (and Side B for that matter) is 8.
← Didn't Know|Knew It →
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
Tap to reveal answer
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
← Didn't Know|Knew It →
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
Tap to reveal answer
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
← Didn't Know|Knew It →
An equilateral triangle has a perimeter of 39in. Find the length of one side.
An equilateral triangle has a perimeter of 39in. Find the length of one side.
Tap to reveal answer
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
← Didn't Know|Knew It →
For an equilateral triangle, Side A measures and Side B measures . What is the length of Side A?
For an equilateral triangle, Side A measures
Tap to reveal answer
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for .
You now know that , but this is not your answer. The question asked for the length of Side A, so you need to plug 3 into that equation.
So the length of Side A (and Side B for that matter) is 8.
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for
You now know that
So the length of Side A (and Side B for that matter) is 8.
← Didn't Know|Knew It →
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
Tap to reveal answer
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
← Didn't Know|Knew It →
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
Tap to reveal answer
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
← Didn't Know|Knew It →
An equilateral triangle has a perimeter of 39in. Find the length of one side.
An equilateral triangle has a perimeter of 39in. Find the length of one side.
Tap to reveal answer
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
← Didn't Know|Knew It →
For an equilateral triangle, Side A measures and Side B measures . What is the length of Side A?
For an equilateral triangle, Side A measures
Tap to reveal answer
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for .
You now know that , but this is not your answer. The question asked for the length of Side A, so you need to plug 3 into that equation.
So the length of Side A (and Side B for that matter) is 8.
First you need to recognize that for an equilateral triangle, all 3 sides have equal lengths.
This means you can set the two values for Side A and Side B equal to one another, since they measure the same length, to solve for
You now know that
So the length of Side A (and Side B for that matter) is 8.
← Didn't Know|Knew It →
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
One angle of an equilateral triangle is 60 degrees. One side of that triangle is 12 centimeters. What are the measures of the two other angles and two other sides?
Tap to reveal answer
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
An equilateral triangle is one in which all three sides are congruent. It also has the property that all three interior angles are equal. In other words, all three angles of an equilateral triangle are always 60°. Since all sides are congruent, the other two sides both measure 12 centimeters.
← Didn't Know|Knew It →
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
If an equilateral triangle has a perimeter of 18in, what is the length of one side?
Tap to reveal answer
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
To find the perimeter of an equilateral triangle, we will use the following formula:
where a is the length of any side of the triangle. Because an equilateral triangle has 3 equal sides, we can use any side in the formula. To find the length of one side of the triangle, we will solve for a.
Now, we know the perimeter of the equilateral triangle is 18in. So, we will substitute.
Therefore, the length of one side of the equilateral triangle is 6in.
← Didn't Know|Knew It →
An equilateral triangle has a perimeter of 39in. Find the length of one side.
An equilateral triangle has a perimeter of 39in. Find the length of one side.
Tap to reveal answer
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
An equilateral triangle has 3 equal sides. So, to find the length of one side, we will use what we know. We know the perimeter of the equilateral triangle is 39in. So, we will look at the formula for perimeter. We get
where a is the length of one side of the triangle. So, to find the length of one side, we will solve for a. Now, as stated before, we know the perimeter of the triangle is 39in. So, we will substitute and solve for a. We get
Therefore, the length of one side of the equilateral triangle is 13in.
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