SOLUTION: evaluate -2a+6b when a = 6 and b =-3

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Question 153920: evaluate -2a+6b when a = 6 and b =-3
Found 2 solutions by checkley77, Edwin McCravy:
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
-2a+6b when a = 6 and b =-3
-2*6+6*-3
-12-18=-30

Answer by Edwin McCravy(20059) About Me  (Show Source):
You can put this solution on YOUR website!
Edwin's solution:
evaluate -2a%2B6b when a+=+6 and b+=-3

-2a%2B6b

Replace the a by %286%29
Replace the b by %28-3%29

-2%286%29%2B6%28-3%29

Multiply -2 by %286%29 and get %28-12%29.
So we replace the -2%286%29 by %28-12%29

%28-12%29%2B6%28-3%29

Multiply 6 by %28-3%29 and get %28-18%29.
So we replace the 6%28-3%29 by %28-18%29

%28-12%29%2B%28-18%29

Use the rule for adding two signed numbers with
like signs:

-30

Edwin