SOLUTION: Solve for a, b, and c in the following system of equations: 4b - c = -10 a - 2b = 5 3a + 4c = -11

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Question 327945: Solve for a, b, and c in the following system of equations:
4b - c = -10
a - 2b = 5
3a + 4c = -11
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.4b+-+c+=+-10
2.a+-+2b+=+5
3.3a+%2B+4c+=+-11
Eliminate one of the variables.
From eq. 2,
a=2b%2B5
Substitute into eq. 3,
+3%282b%2B5%29%2B4c=-11
6b%2B15%2B4c=-11
6b%2B4c=-26
4.3b%2B2c=-13
Multiply eq. 1 by (2) and add to eq. 4 to elminate c.
8b-2c%2B3c%2B2c=-20-13
11b=-33
highlight%28b=-3%29
Then from eq. 4,
-9%2B2c=-13
2c=-4
highlight%28c=-2%29
And finally from eq. 2,
a=2%28-3%29%2B5
highlight%28a=-1%29