Question

If f(x) = |x + 8|, find f(–11).

19


–3


3


–19

2. If f(x) = |x – 5| + 3, find f(2).



4


11


0


6

Answer 1

Explanation:

1) Plug in the number to the equation

f(-11) = |-11 + 8|

= |-3|

absolute value makes it positive so the answer is 3

2) Plug in the number to the equation

f(2) = |2 -5| +3

do the absolute value before adding the 3

|-3| + 3 = 3 + 3

= 6

Answer 2

1. f(-11) = 3.

2. f(2) = 6.

Explanation:

Note the vertical lines around the x + 8 is the absolute value which is always positive.

f(x) = |x + 8| so f(-11) = |-11 + 8|

= |-3|

= 3 (answer).

If f(x) = |x – 5| + 3, find f(2).

f(2) = | 2 - 5| + 3

= |-3| + 3

= 3 + 3

= 6 (answer)