How do you solve the following system: 2x-y=7, 2x +5y = 5 ?

1 Answer
Alan P.
Dec 22, 2015

(x,y)=(3 1/3, -1/3)

Explanation:

Given:
[1]color(white)("XXX")2x-y=7
[2]color(white)("XXX")2x+5y=5

Subtract [2] from[1]
[3]color(white)("XXX")-6y=2

Divide both sides by (-6) (and reduce the resulting fraction)
[4]color(white)("XXX")y=-1/3

Substitute (-1/3) for y in [1]
[5]color(white)("XXX")2x-(-1/3)=7

Subtract 1/3 from both sides
[6]color(white)("XXX")2x=6 2/3

Divide both sides by 2
[7]color(white)("XXX")x=3 1/3

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