All GED Math Resources
Example Questions
Example Question #1 : Similar Triangles And Proportions
Which of the following statements is not a consequence of the statement
?
is simply a restatement of , since the names of the corresponding vertices of the similar triangles are still in the same relative positions.
is a consequence of , since corresponding angles of similar triangles are, by definition, congruent.
is a consequence of , since corresponding sides of similar triangles are, by definition, in proportion.
However, similar triangles need not have congruent corresponding sides. Therefore, it does not necessarily follow that . This is the correct choice.
Example Question #2 : Similar Triangles And Proportions
Which of the following statements follows from the statement ?
The similarity of two triangles implies nothing about the relationship of two angles of the same triangle. Therefore, can be eliminated.
The similarity of two triangles implies that corresponding angles between the triangles are congruent. However, because of the positions of the letters, in corresponds to , not , in , so . The statement can be eliminated.
Similarity of two triangles does not imply any congruence between sides of the triangles, so can be eliminated.
Similarity of triangles implies that corresponding sides are in proportion. and in correspond, respectively, to and in . Therefore, it follows that , and this statement is the correct choice.
Example Question #1 : Similar Triangles And Proportions
Note: Figure NOT drawn to scale.
Refer to the above diagram. If , which of the following is false?
is a right angle
Suppose .
Corresponding angles of similar triangles are congruent, so . Also, , so, since is a right angle, so is .
Corresponding sides of similar triangles are in proportion. Since
,
the similarity ratio of to is 3.
By the Pythagorean Theorem, since is the hypotenuse of a right triangle with legs 6 and 8, its measure is
.
, so is a true statement.
But , so is false if the triangles are similar. This is the correct choice.
Example Question #2 : Similar Triangles And Proportions
Note: Figures NOT drawn to scale.
Refer to the above figures. Given that , evaluate .
By the Pythagorean Theorem, since is the hypotenuse of a right triangle with legs 6 and 8, its measure is
.
The similarity ratio of to is
.
Likewise,
Example Question #2 : Similar Triangles And Proportions
Note: Figures NOT drawn to scale.
Refer to the above figures. Given that , give the area of .
Corresponding angles of similar triangles are congruent, so, since is right, so is . This makes and the legs of a right triangle, so its area is half their product.
By the Pythagorean Theorem, since is the hypotenuse of a right triangle with legs 6 and 8, its measure is
.
The similarity ratio of to is
.
This can be used to find and :
The area of is therefore
.
Example Question #2 : Similar Triangles And Proportions
In the figure below, the two triangles are similar. Find the value of .
Since the two triangles are similar, we know that their corresponding sides must be in the same ratio to each other. Thus, we can write the following equation:
Now, solve for .