SOLUTION: 2x-3y=18 5x+9y=-10

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Question 1032541: 2x-3y=18
5x+9y=-10
Answer by ikleyn(52781) About Me  (Show Source):
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2x - 3y =  18,     (1)
5x + 9y = -10.     (2)

Multiply equation (1) by 5 (both sides) and equation (2) by 2. You will get

10x - 15y =  90,   (3)
10x + 18y = -20.   (4)

Now distract equation (3) from equation (4) (both sides). You will get

-15y - 18y = 90 -(-20),

-33y = 110,

y = 110%2F%28-33%29 = -110%2F33 = -31%2F3.

Then from (1)  x = %2818%2B3y%29%2F2 = 18-10%2F2 = 8%2F2 = 4.

Answer. x = 4, y = -31%2F3.