Question

Can someone help me please to see if I did this correctly ?
Suppose that the functions r and s are defined for all real numbers x as follows.

r(x)=2x+2
s(x)=x-2
Write the expressions for (s-r)(x) and (s+r)(x) and evaluate (s*r)(-2)

(s-r)(x)= -x-7
(s+r)(x)=3x-3)
(s*r)(-2)=

I'm having a little trouble on the last part on how to solve it.

Answer 1

how did you get `(s-r)(x)= -x-7` ?

Answer 2

I kept getting 61 but it said it was wrong I placed it in my calculator and I know that's right because it told me I was write for -x-7 but I seem to be getting the last part wrong.

Answer 3

right not write

Answer 4

x-2x = -x, that is correct
-2-2 = -7 is not correct

Answer 5

But it told me I was correct....

Answer 6

the only thing it told me I was wrong on was the last part ...

Answer 7

there has to be a typo somewhere

Answer 8

I don't see it I copied and paste it want me to send you the screen shot?

Answer 9

sure

Answer 10

This is what it says

Answer 11

I see, it should be s(x) = x-5

Answer 12

Nope because before I put that and it told me that they need to be simplified further and that's what I got when I simplified it ...

Answer 13

No I meant the original problem

Answer 14

instead of s(x) = x-2 the actual problem is s(x) = x-5

Answer 15

So it should be this ?

x-5*(2x+2)?

Answer 16

Then I would solve it that way?

Answer 17

(s*r)(-2)= s(-2)*r(-2)

what are the values of s(-2) and r(-2) ?

Answer 18

Um I'm not sure...

Answer 19

s(x) = x-5
s(-2) = -2 - 5 ... replace every x with -2
s(-2) = ??

Answer 20

-2-5*(2(-2)+2)?

Answer 21

you need parenthesis around the `-2-5`

Answer 22

so (-2-5)*(2(-2)+2)?

Answer 23

yeah

Answer 24

14?

Answer 25

yep

Answer 26

Alright thank you!

Answer 27

s(x) = x-5
s(-2) = -2 - 5 ... replace every x with -2
s(-2) = -7


r(x) = 2x+2
r(-2) = 2(-2)+2
r(-2) = -2


(s*r)(-2)= s(-2)*r(-2)
(s*r)(-2)= -7*(-2)
(s*r)(-2)= 14

Answer 28

Thanks!