3(7r+3)=-117

Question

can you help me on my math question & solve them for me so i could understand 

Answer 1

i would start by distributing the "3"

3(7r + 3) = -117

21r + 9 = -117

then you want to isolate the term "r" by subtracting 9 and dividing by 21

r = (-117 - 9) / 21

r = -6

Answer 2

Hi Andy,

 

We are looking to solve for r in the equation.

 

First we smplify the left hand side , 3(7r +3) as 3*7r + 3*3 = 21r +9 

So the given equation is

21r +9 = -117 

 

Subtracting 9 from both sides ,

 21r +9 -9 = -117-9

or r = (-117-9)/21 

or r = -126/21 = -6

 

So r = -6 ( and we should check if -6 satisfies the equation given to be sure)