SOLUTION: How do i use linear combinations to solve the system of this linear equation 2a+6z=4 3a-7z=6

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Question 510991: How do i use linear combinations to solve the
system of this linear equation
2a+6z=4
3a-7z=6
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
2a+6z=4
3a-7z=6
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Multiply thru the 1st equation by 2.
Multiply thru the 2nd equation by 3.
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6a + 18z = 12
6a - 14z = 12
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Subtract and solve for "z":
32z = 0
z = 0
----
Solve for "a":
2a + 6z = 4
2a + 6*0 = 4
2a = 4
a = 2
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Cheers,
Stan H.
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