Question

Solve the following system of equations by using elimination: 3x - y = -1 x + y = 13

Answer 1

Solution

For this case we have the following system of equations:

3x-y =-1 (1)

x +y= 13 (2)

Solving x from the (2) equation we have:

x=13-y (3)

Replacing (3) into (1) we got:

3(13-y) -y= -1

Solving for y we have:

39 -3y -y = -1

4y = 40

y= 10

And solving for x we got:

x= 13-10 = 3