Question

Let f(x) = -2x - 7 and g(x) = -4x + 3. Find (f ° g)(-5).
A. 23
B. –53
C. –9
D. 3

Answer 1

To find (fog)(x),u replace x in f(x) with entire g(x) expression,then replace x in the answer with -5 to get (fog)(-5)....try it

Answer 2

I have no idea what your talking about. I cant do that. ha

Answer 3

see,here i am replacing x in f(x) with g(x)
f(g(x))=-2(-4x+3)-7=.....?
now can u simplify this?

Answer 4

-6-4x?

Answer 5

f(g(x))=-2(-4x+3)-7=(-2)(-4x)+(-2)3-7=8x-6-7=8x-13.....now put x=-5

Answer 6

Nevermind. I cant do all that!

Answer 7

u have to just put x=-5 in 8x-13
like this 8(-5)-13= -40-13=-53.....there u go...

Answer 8

Oh. I thought you were trying to give me some huge equation at first. thank you