Respuesta :

Answer:

r = -21

Step-by-step explanation:

-2(r + 9)

-2 (-21 + 9)

-21 + 9 = -12

-2(-12)

= 24

Answer:

-21

Step-by-step explanation:

Detailed explanation:

24 = -2(r + 9)

First, I did distributive property

24 = -2r -18

Now I will add 18 to both sides

42 = -2r

Now I will divide both sides by -2

-21 = r

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