### All SAT II Math I Resources

## Example Questions

### Example Question #1 : Absolute Value

Define an operation on the set of real numbers as follows:

For any two real numbers

Evaluate the expression

**Possible Answers:**

**Correct answer:**

Substitute in the expression:

### Example Question #1 : Absolute Value

Simplify the following expression:

**Possible Answers:**

**Correct answer:**

To simplify, we must first simplify the absolute values.

Now, combine like terms:

### Example Question #3 : Absolute Value

Solve for .

**Possible Answers:**

**Correct answer:**

To solve for x we need to make two separate equations. Since it has absolute value bars around it we know that the inside can equal either 7 or -7 before the asolute value is applied.

### Example Question #4 : Absolute Value

The absolute value of a negative can be positive or negative. True or false?

**Possible Answers:**

True

False

**Correct answer:**

False

The absolute value of a number is the points away from zero on a number line.

Since this is a countable value, you cannot count a negative number.

This makes all absolute values positive and also make the statement above false.

### Example Question #1 : Absolute Value

Consider the quadratic equation

Which of the following absolute value equations has the same solution set?

**Possible Answers:**

None of the other choices gives the correct response.

**Correct answer:**

Rewrite the quadratic equation in standard form by subtracting from both sides:

Factor this as

where the squares represent two integers with sum and product 14. Through some trial and error, we find that and work:

By the Zero Product Principle, one of these factors must be equal to 0.

If then ;

if then .

The given equation has solution set , so we are looking for an absolute value equation with this set as well.

This equation can take the form

This can be rewritten as the compound equation

Adding to both sides of each equation, the solution set is

and

Setting these numbers equal in value to the desired solutions, we get the linear system

Adding and solving for :

Backsolving to find :

The desired absolute value equation is .

### Example Question #1 : Absolute Value

What is the value of: ?

**Possible Answers:**

**Correct answer:**

Step 1: Evaluate ...

Step 2: Apply the minus sign inside the absolute value to the answer in Step 1...

Step 3: Define absolute value...

The absolute value of any value is always positive, unless there is an extra negation outside (sometimes)..

Step 4: Evaluate...

### Example Question #1 : Absolute Value

Solve:

**Possible Answers:**

**Correct answer:**

Divide both sides by negative three.

Since the lone absolute value is not equal to a negative, we can continue with the problem. Split the equation into its positive and negative components.

Evaluate the first equation by subtracting one on both sides, and then dividing by two on both sides.

Evaluate the second equation by dividing a negative one on both sides.

Subtract one on both sides.

Divide by 2 on both sides.

The answers are:

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