Question

slove the linear equestion 2x+3y=1, 5X+7y=3.

2) 2X+4y=10 and 3x+6y=15

3) 2x+3y=3, x-2=5 and 3x+2y=7

Answer 1

2x + 3y = 1 -->(-5)
5x + 7y = 3 -->(2)
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-10x - 15y = -5 (result of multiplying by -5)
10x + 14y = 6 (result of multiplying by 2)
----------------add
-y = 1
y = -1
now sub -1 in for y in either equation to find x.
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2x + 4y = 10 reduces to x + 2y = 5
3x + 6y = 15 reduces to x + 2y = 5
same equation, same line, INFINITE SOLUTIONS
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In these 3 equations....is there supposed to be a y term in the 2nd one ?

Answer 2

yep