Question 508423: Solve using the elimination method. Ff the system has no solution or an infinite number of solutions, state it -12x+27y=60, -6x-6y=30
Answer by swincher4391(1107)   (Show Source):
You can put this solution on YOUR website! So, we are given two equations. -12x +27y = 60 and -6x-6y = 30
Let's line these up
-12x + 27y = 60
-6x -6y = 30
Notice that -12 is a multiple of -6 in our x-column.
So let's multiply the ENTIRE bottom equation by -2. Then we will add the two equations together. (Alternatively, we could multiply by 2 and subtract)
-12x + 27y = 60
-2(-6x -6y = 30)
-12x + 27y = 60
12x + 12y = -60
39y = 0
y = 0
Now substitute y =0 into any original equation to find x.
Let's use the 2nd one.
-6x - 6(0) = 30
-6x = 30
x = -5
So our solution is (-5,0) or x=-5 y =0
Hope this helped!
Please e-mail me at onlyyourmathtutor@yahoo.com if this answer was not clear enough.
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