SOLUTION: Chapter The Elimination Method 6x-5y=3 -12x+8y=5

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Question 74372: Chapter The Elimination Method
6x-5y=3
-12x+8y=5
Found 2 solutions by jim_thompson5910, checkley75:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
6x-5y=3
-12x%2B8y=5
We need to get the x coefficients the same number but opposite signs so they cancel. We can do this by multiplying the 1st equation by 2.
2%286x-5y%29=2%283%29
12x-10y=6
Add this to -12x%2B8y=5
12x-10y=6
+-12x%2B8y=5
----------------
0x-2y=11
2y=11Solve for y
y=-11%2F2
Use this info to solve for x
6x-5%28-11%2F2%29=3
6x%2B55%2F2=3
6x=3-55%2F2
6x=6%2F2-55%2F2
6x=-49%2F2
x=%28-49%2F2%29%2F6
x=-49%2F12
So the solution is (-49/12,-11/2)

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
MULTIPLY THE FIRST EQUATION BY 2 & ADD.
12X-10Y=6
-12X+8Y=5
-----------------------------------------
-2Y=11
Y=11/-2
Y=-11/2 ANSWER. NOW SUBSTITUTE (-11/2) FOR Y & SOLVE FOR X
-12X+8(-11/2)=5
-12X-88/2=5
-12X-44=5
-12X=5+44
-12X=49
X=49/-12
X=-49/12 ANSWER.
PROOF
(6*-49/12-5*-11/2)=3
(-294/12+55/2)=3
(-294+55*6)/12=3
(-294+330)/12=3
36/12=3
3=3