Question 833305: solve : 3x+5y=7 and 4x-3y=-10. if (a,b) is the solution, what is the sum of a and b?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! solve : 3x+5y=7 and 4x-3y=-10. if (a,b) is the solution, what is the sum of a and b?
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3x + 5y = 7
4x - 3y = -10
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Modify for elination:
12x + 20y = 28
12x - 9y = -30
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Subtract and solve for "y":
29y = 58
y = 2
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Solve for "x":
3x + 5y = 7
3x + 10 = 7
3x = -3
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x = -1
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(a,b) = (-1,2)
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Ans: a*b = -2
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Cheers,
Stan H.
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