Question

WGiven the function f(x) = 0.5|x – 4| – 3, for what values of x is f(x) = 7? x = –24, x = 16 x = –16, x = 24 x = –1, x = 9 x = 1, x = –9

Answer 1

x = 24, x = -16

Explanation:

Given the function f(x) = 0.5|x – 4| – 3, we are to find the values of x for f(x) = 7

Substitute f(x) = 7 into the expression;

7 = 0.5|x – 4| – 3

For the positive function

7 = 0.5(x – 4) – 3

7 = 0.5x - 2 - 3

7 = 0.5x - 5

7+5 = 0.5x

12 = 0.5x

12 = x/2

Swap

x/2 = 12

x = 12 * 2

x = 24

For the negative function

7 = 0.5-(x – 4) – 3

7 = 0.5(-x +4) - 3

7 = -0.5x +2 - 3

7 = -0.5x - 1

7+1 = -0.5x

8 = -x/2

Swap

-x/2 = 8

-x = 8 * 2

-x = 16

x = -16

Hence the required values of x are -16 and 24