Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
4. Solving Absolute Value Equations
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Exercise 54 Page 34

What is the opposite of a-b?

Always

Practice makes perfect
The absolute values of any real number and its opposite are always the same. The reason is that they are both an an equal distance from 0 on a number line. | a| = |- a| Therefore, the absolute value of a-b is equal to the absolute value of its opposite, which we can write as -(a-b). Let's distribute the negative sign and simplify the expression.
-(a-b)
- a-(- b)
- a+b
b-a
Since b-a is the opposite of a-b, we get the following absolute value equation. |a-b|=|b-a| We can write a conclusion.

If a and b are real numbers, then |a-b| is always equal to |b-a|.