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

Expert Answers

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To do elimination, you need to make it so that one of the variable terms will cancel itself out.  In other words, you need to be able to add two of one term together and get 0.

In this case, you can do this by making both one x term be 3x and the other be -3x..  The way to do that is to multiply the second equation by -1.5.

So then you would have the second equation being

3y - 3x = 12

Now you add the two equations together.  That gets you

6y = -18

Which makes y = -3 when you divide both sides by 6.

Now you plug this value of y into one of the equations to solve for x.  We'll do the second equation.

6 + 2x = -8

2x = -14

x = -7

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