How do you solve -4x+y=-11 and 2x-3y=5?

1 Answer
Alan P.
Nov 30, 2015

(x,y) = (14/5,1/5)

Explanation:

Given:
[1]color(white)("XXX")-4x+y=-11
[2]color(white)("XXX")2x-3y=5

Multiply [2] by 2 giving x a coefficient of the same magnitude as in [1]
[3]color(white)("XXX")4x-6y =10

Add [1] and [3], eliminating the x term
[4]color(white)("XXX")-5y = -1

Divide both sides of [4] by (-5)
[6]color(white)("XXX")y=1/5

Multiply [1] by 3 giving y a coefficient of the same magnitude as in [2]
[7]color(white)("XXX")-12x+3y=-33

Add [2] and [7], eliminating the y term
[8]color(white)("XXX")-10x = -28

Divide both sides of [8] by (-10)
[9]color(white)("XXX")x=14/5

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