Exercise 9 Page 211

An absolute value measures an expression's distance from a midpoint on a number line. |b|= 1/2 This equation means that the distance is 12, either in the positive direction or the negative direction. |b|= 12 ⇒ b& = 1/2 b& = - 1/2 In this case, our absolute value expression is only the variable b, so our equivalent pair of linear equations do not need any more simplifying. Now, let's graph these solutions on a number line.

To check our solutions, we will substitute them into the equation.

Since substitution resulted in an identity, b= 12 is a correct solution.

Since the substitution resulted in an identity, b=- 12 is also a correct solution.