SOLUTION: What is the answer to these systems of equations using addition to eliminate one of the variables? 4a-6b=15 6a-4b=10

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Question 133609: What is the answer to these systems of equations using addition to eliminate one of the variables?
4a-6b=15
6a-4b=10
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
4a-6b=15
6a-4b=10
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Multiply 1st by 6 and multiply 2nd by 4 to get:
24a - 36b = 90
24a - 16b = 40
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subtract 1st from 2nd to get:
20b = -50
b = -5/2
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Substitute to solve for "a":
4(-5/2) -6b = 90
-10 -6b = 90
-6b = 100
b = -16.666667
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Cheers,
Stan H.