SOLUTION: 2y-3x=18 and x+y=4

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Question 107369: 2y-3x=18 and x+y=4
Answer by blueskyy(3) About Me  (Show Source):
You can put this solution on YOUR website!
x + y = 4
so, y = 4- x
2y - 3x = 18
or 2y = 18 + 3x
or 2(4-x) = 18 + 3x
or 8 - 2x = 18 + 3x
or 8 - 18 = 3x + 2x
or -10 = 5x
or -2 = x
so, y = 4-(-2)
so, y = 4+2 = 6

so, x= -2 ; y =6


check :
2y - 3x

2y = 2*6 = 12
3x = 3 *(-2) = -6
2y - 3x = 12 - (-6)
= 12 +6
= 18