Solve the following systems of linear equations by elimination, showing all work: 3y+3x=-30 -2y+2x=-8help

First of all, we have to take a look to the both
equations, to see what unknown could be canceled. In our case, it is obviously that the
unknown x could be canceled easier than y, because the coefficients of the unknown x
have opposite signs.

After choosing what unknown could be
canceled, we have to find out which is the common denominator of the coefficients of the
unknown x. In this case is 2*3=6.

The next step is to
multiply the first equation with 2 and the second equation with 3, after that the both
equations will be added.

2(3y+3x) +
3(-2y+2x)=-60-24

6y+6x-6y+6x=-84

After
reducing similar terms, we'll
have:

12x=-84

x=-7

After
finding the unknown x, we'll substitute it into what equation we
choose.

3y+3x=-30

3y+3(-7)=-30

3y=-30+21

3y=-9

y=-3