SOLUTION: 4ax+by=11ab 8ax-5by=ab Solve for x and y

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Question 1086832: 4ax+by=11ab
8ax-5by=ab
Solve for x and y
Found 3 solutions by Fombitz, Boreal, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply eq. 1 by 2 and subtract from eq. 2,
8ax-5by-8ax-2by=ab-22ab
-7by=-21ab
y=3a
Now use either equation to solve for x.

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
4ax+by=11ab
8ax-5by=ab
88ax-55by=11ab
-4ax-by=-11ab, multiplying the first by -1
84ax-56by=0
84ax=56by
3ax=2by
y=3ax/2b
x=(2/3)(by/a) or y=2by/3a
=================
Let x=2 and y=3
8a+3b=66
16a-15b=6
-16a-6b=-132
-21b=-126
b=6
8a+18=66
a=6
checks with second equation.
since a and b are equal, y=3

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

4ax+by=11ab
8ax-5by=ab
Solve for x and y
Correct answer: highlight_green%28matrix%282%2C3%2C+x%2C+%22=%22%2C+2b%2C+y%2C+%22=%22%2C+3a%29%29