How do you solve x - 2y = -6x2y=6 and -x + y = 2x+y=2?

3 Answers
Jun 9, 2017

I got:
x=2x=2
y=4y=4

Explanation:

Have a look:

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Jun 9, 2017

x=2 and y=4x=2andy=4

Explanation:

Make xx the subject of both equations:

x= 2y-6" and "x= y-2x=2y6 and x=y2

The value of xx is the same, so if:

" "x = x x=x then:
2y-6 = y-2" "larr2y6=y2 solve for yy

2y-y= -2+62yy=2+6

y =4y=4

x = 2(4) -6x=2(4)6

x=8-6x=86

x=2x=2

Jun 9, 2017

x=2x=2
y=4y=4

Explanation:

We could also solve this problem using substitution.

Solve the 1st equation for xx:

x-2y=-6x2y=6

x=2y-6x=2y6

Substitute the above into the 2nd equation and solve for yy:

-x+y=2x+y=2

-(2y-6)+y=2(2y6)+y=2

-2y+6+y=22y+6+y=2

-y=-4y=4

y=4y=4

Substitute yy into the 1st equation and solve for xx:

x-2y=-6x2y=6

x-2(4)=-6x2(4)=6

x=2x=2