Question

HELP PLEASE!

The functions r and s are defined as follows.

r(x)=-5x-5
s(x)=3x+1

Find the value of s(r(-4)).

Answer 1

Answer: 46

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Step 1 is to compute the value of r(-4)

r(x) = -5x-5

r(-4) = -5(-4)-5 ... replace every x with -4

r(-4) = 20-5

r(-4) = 15

Now we can do replacements. We can replace the "r(-4)" with 15 because of the last equation above.

So we go from s(r(-4)) to s(15)

Plug x = 15 into the s function

s(x) = 3x+1

s(15) = 3*15+1

s(15) = 45+1

s(15) = 46

In the end,

s(r(-4)) = 46