How do you solve the following system of equations?: x+y= -2 , 4x+3y=8 ?

2 Answers
Feb 2, 2016

the answer: x=14 and y = -16

Explanation:

In the two equations, get y alone. So you have:

y= -x-2 and

y= -4/3 x +8/3.

Then you set the two equations equal to each other:

-x-2= -4/3 x +8/3.

Then you solve for x, and you get x=14. You then substitute 14 into both equations to get y, and then you have your coordinates.

Feb 2, 2016

Solve by substitution and elimination:

x+y=-2

4x+3y=8

We can eliminate 4x from the second equation by x from the first equation if we multiply it by -4 to get -4x:

rarr-4(x+y=-2)

rarr-4x-4y=8

Now add both of the equations:

rarr(-4x-4y=8)+(4x+3y=8)

rarr-1y=16

rarr-y=16

So,if -y =16 then ,y =-16

Now substitute the value of y to the first equation:

x+(-16)=-2

x-16=-2

x=-2+16=14

So,(x,y)=(14,-16)

You can check the answer and it will be correct! :)