Question

3x-4y=-9 -6x+4y=-6 solve with elimination

Answer 1

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Answer 2

So let's write this out first to make our lives easier\[3x-4y=9\] \[-6x+4y=6\]

Answer 3

Right away you can see that if we add the two equations to find one master equation, the y's cancel out

Answer 4

So adding the two equations you get \[-3x+0y=15\] or simply\[-3x=15\]

Answer 5

Now it's extremely easy to find x, just divide both sides by -3 to get -5

Answer 6

What you want to do to find the y coordinate is to plug in your x value into one of your equations and solve for y

Answer 7

Whoops the first equation is -9 not 9 haha my bad your x value is actually -3 when you change your values accordingly you get x=-3

Answer 8

or rather just 5

Answer 9

Anyway so once you plug in your x value of 5 into let's say the first equation (it can be either of the two) you get \[3(5)-4y=-9\]

Answer 10

subtract 15 from both sides to get -4y=-24

Answer 11

then solve for y, which is 6

Answer 12

So your solution is (x,y)=(5,6)