Question 999071: i need help with this problem please:
4x+4y=8
2x+y=2
another elimation/addition systems of equations problem.
i just dont know what to multiply to the first equation to make the variables. im having issues with that. help.
Found 2 solutions by Alan3354, ikleyn:
Answer by Alan3354(69443)   (Show Source):
You can put this solution on YOUR website! i need help with this problem please:
4x+4y=8
2x+y=2
another elimation/addition systems of equations problem.
i just dont know what to multiply to the first equation to make the variables. im having issues with that.
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You can multiply the 2nd eqn by 2, then eliminate x. Or by 4 and eliminate y.
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I would divide the 1st eqn by 4. I prefer smaller coefficients generally.
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Divide the 1st eqn by 4, then subtract.
Answer by ikleyn(52785)  (Show Source):
You can put this solution on YOUR website! .
4x + 4y = 8 (1)
2x + y = 2 (2)
Multiply the equation (2) by 2 (both sides). You will get
4x + 4y = 8 (1')
4x + 2y = 4 (2')
Distract (2') from (1') (both sides). You will get
(4x - 4x) + (4y - 2y) = 8 - 4, or
0*x + 2y = 4, or
2y = 4.
Hence, y =  = 2.
Now you can easily find x from 4x + 4y = 8.
Namely, 4x = 8 - 4y = 8 - 4*2 = 0, hence, x = 0.
Answer. x=0, y=2
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