Evaluate 5 (x _ 4) for x = 8

5 (x - 4)

You can use the distributive propery to solve this one.

First list the terms in the parenthesis:

x - 4

then multiply both by five

5x - 20

now substitute

(5 * 8) - 20

(40) - 20

40 - 20

20

Your answer is 20