SOLUTION: How do I solve the equations 3a+9b=8b-a and 5a-10b=4a-9b+5 using elimination?

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Question 935680: How do I solve the equations 3a+9b=8b-a and 5a-10b=4a-9b+5 using elimination?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

the equations
3a%2B9b=8b-a and
5a-10b=4a-9b%2B5 you can solve as a system using elimination
__________________
3a%2B9b=8b-a........eq.1 move all terms from the right side to the left
5a-10b=4a-9b%2B5........eq.2
________________________
3a%2Ba%2B9b-8b=0........eq.1
5a-4a-10b%2B9b=5........eq.2
________________________

4a%2Bb=0........eq.1
a-b=5........eq.2
________________________...add both to eliminate b
4a%2Bcross%28b%29%2Ba-cross%28b%29=5
5a=5
highlight%28a=1%29
go to 4a%2Bb=0........eq.1 substitute 1 for a
4%2A1%2Bb=0........eq.1
4%2Bb=0
highlight%28b=-4%29