SOLUTION: a-15=b 3a=b-15 What's the a and b?

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Question 686956: a-15=b
3a=b-15
What's the a and b?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

a-15=b.......eq.1
3a=b-15.....eq.2
______________________
3a=b-15.....eq.2..substitute b from eq.1
3a=a-15-15......solve for a
3a-a=-30
2a=-30
a=-30%2F2
highlight%28a=-15%29
go back to eq.1 and solve for b
a-15=b.......eq.1
-15-15=b
highlight%28b=-30%29