Answer:
I'll assume "S2x+3y=-12" is actually 2x+3y=-12 and that the question is to solve for x and y.
x = -(9/5)
y = -(14/5)
Step-by-step explanation:
2x+3y=-12
4x-4y=4
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2x+3y=-12
8x+12y=-48 [Multiply the 1st equation by 4]
12x-12y=12 [Multiply the second equation by 3]
20x = -36 [Now we can add the two equations to remoce the y term]
x = -(36/20)
x = -(9/5) [The value for x]
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2x+3y=-12 [Take either equation and s=use x=-(9/5) to find y]
2(-9/5)+3y=-12
-(18/5) + 3y = -12
+ 3y = -12 + (18/5)
y = -4 + (6/5)
y = -(20/5)+(6/5)
y = -(14/5) [This is the value of y that will work for both equations]
These equations both have the point (-9/5, -14/5) in common: they intersect here.
This problem can also be solved by graphing each equation and finding the point they inersect on the graph (attached).
