Question

Given the function f(x) = 2(x + 4), find x if f(x) = 20.

Answer 1

solve accordingly

Answer 2

20=2x+4.......20-4 = 2x.......16=2x....x =?

Answer 3

so um...

Answer 4

16/2 = x

Answer 5

8

Answer 6

i lied.... 2x +8 = 20.......20-8=2x......12=2x....x=?

Answer 7

where in the world did 8 come from?

Answer 8

distributive property... 2(x+4) = 2x+8

Answer 9

but arent you not supposed to distribute with a function?

Answer 10

yes, the function equals both 20 and 2x+8, so you set them equal to each other to find x

Answer 11

you want to get x all by its self