SOLUTION: How do you solve 12r-18=13r+18

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Question 83329: How do you solve 12r-18=13r+18
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The goal of solving for a variable is to isolate the variable

12r-18=13r%2B18 Start with the given equation

12r%2Bcross%28-18%2B18%29=13r%2B18%2B18 Add 18 to both sides

12r-13r=cross%2813r-13r%29%2B36 Subtract 13r from both sides

-1%28-r%29=-1%2836%29 Multiply both sides by -1 to make r positive

So we get the answer

r=-36


Check:
12%28-36%29-18=13%28-36%29%2B18

-432-18=-468%2B18

-450=-450 works. This verifies our answer.