How do you solve x+y=3 3x-y=17?

1 Answer
Feb 26, 2018

x=5, y=-2

Explanation:

We have a system of equations in x,y

{: (x+y =3 ), (3x-y =17) :}}

Add the 1st eqn. to the 2nd.

4x=20 rArr x=5

Solve for y using the 1st eqn.

y=3-x=3-5=-2

So the set of solutions is (5,-2)