Question

Solve by elementation

Answer 1

I don't understand can you show have to do this pleas

Answer 2

Elimination occurs when you add or subtract each equation in order to isolate one variable.

In this case, the first equation can be multiplied by 3. This will get you a -12x in one equation and a 12x in the other.

-12x - 9y = -42
12x + 5y = 2

Now add the second equation to the first to cancel the -12x and 12x.

-4y = -40

Now divide both sides by -4.

y = 10

Plug in the y value for one of the original equations and solve.

12x + 5(10) = 2
12x + 50 = 2
12x = -48
x = -4

Your solution set is (-4, 10)