Question 707913: can you please help me with this problem:
-12x-10y=90
-6x-y=9
what is the x and y values?
can you show all the steps please? :)
Answer by jim_thompson5910(35256)   (Show Source):
You can put this solution on YOUR website! Multiply both sides in equation 2 by the number -2 to get
-6x-y=9
-2(-6x-y)= -2*9
12x + 2y = -18
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So the system
-12x-10y=90
-6x-y=9
turns into
-12x-10y=90
12x+2y=-18
Add the equations
-12x-10y=90
12x+2y=-18
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0x-8y=72
So -8y = 72. Solve for y
-8y = 72
y = 72/(-8)
y = -9
Now use this to find x.
-12x-10y=90
-12x-10(-9)=90
-12x+90=90
-12x=90-90
-12x=0
x = 0/(-12)
x = 0
So x = 0 and y = -9
Therefore, the solution as an ordered pair is (0, -9)
If you graphed both equations, you'll see that they intersect at (0, -9) which would give you visual confirmation of the answer.
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