Question

If h(x) = 4x − 8 and j(x) = −x, solve h[j(3)] and select the correct answer below.

−36
−20
1
4

Answer 1

if j(x) = -x, then what is j(3) equal to?

Answer 2

umm idk.. is it j(-3) ?

Answer 3

replace every x in the j(x) function with 3

you're on the right track, but it should be

j(3) = -3

do you see how I got that?

Answer 4

ooh okay yea i see

Answer 5

so \(\Large h[{\color{red}{j(3)}}]\) turns into \(\Large h[{\color{red}{-3}}]\)

this is possible because j(3) = -3. We can replace all of `j(3)` with `-3`

Answer 6

now evaluate h(-3) by plugging x = -3 into the h(x) function

Answer 7

h(-3)= 4(-3)-8 ??

Answer 8

yep now simplify the right hand side

Answer 9

yikes.. idk how to just to the right hand side

Answer 10

4(-3)-8 is the same as 4*(-3)-8

in words it means "4 times -3, then subtract 8"

Answer 11

-20

Answer 12

you can use a calculator or work it out on paper

here's a free calculator that's handy

http://web2.0calc.com/

Answer 13

yes, 4(-3)-8 = -20, so h(-3) = -20

Answer 14

which means h[j(3)] = -20

Answer 15

i always use mathway.com its awesome haha

Answer 16

that works too