SOLUTION: Simultaneous equation help! The answer at the back to this question is (3,-1). The question is: 4x+y=11 3x+2y=7 ??

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Question 1001169: Simultaneous equation help! The answer at the back to this question is (3,-1). The question is:
4x+y=11
3x+2y=7
??

Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi there,
4x+y=11......(1)
3x+2y=7......(2)
Multiply (1) by 3
Multiply (2) by 4
12x + 3y = 33....(1)
12x + 8y = 28....(2)
Subtract (2) from (1)
.....-5y = 5
.....y = -1
Substitute y = -1 into (1)
4x+y=11......(1)
4x + (-1) = 11
4x - 1 = 11
4x = 11 + 1
4x = 12
x = 3
Answer (3, -1)
Hope this helps. :-)