SOLUTION: I have to do elimination with this but I don't know what to multiply it by. I am getting weird fractions but I know it is incorrect.
8x-7y=-6
7x-8y=-9
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-> SOLUTION: I have to do elimination with this but I don't know what to multiply it by. I am getting weird fractions but I know it is incorrect.
8x-7y=-6
7x-8y=-9
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Question 1199812: I have to do elimination with this but I don't know what to multiply it by. I am getting weird fractions but I know it is incorrect.
8x-7y=-6
7x-8y=-9 Found 3 solutions by josgarithmetic, math_tutor2020, ikleyn:Answer by josgarithmetic(39617) (Show Source):
At this point the y terms are -56y and 56y. They add to 0y or simply 0. The y variables are eliminated.
Add the x terms: 64x+(-49x) = 15x
Add the right hand side constants: -48+63 = 15
We arrive at 15x = 15 which solves to x = 1.
Once we determine x, use it to find the value of y.
8x-7y = -6
8*1-7y = -6
8-7y = -6
-7y = -6-8
-7y = -14
y = -14/(-7)
y = 2
The solution is (x,y) = (1,2)
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Check:
Plug x = 1 and y = 2 into the first original equation
8x-7y = -6
8*1-7*2 = -6
8-14 = -6
-6 = -6
That equation is confirmed.
Repeat for the other original equation
7x-8y = -9
7*1-8*2 = -9
7-16 = -9
-9 = -9
Both equations are confirmed.
Another way to check the answer is to use a graphing tool like Desmos or GeoGebra to plot each of the original lines separately
The two lines 8x-7y = -6 and 7x-8y = -9 intersect at (1,2)
8x-7y = -6 in green
7x-8y = -9 in blue
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