SOLUTION: I need hep please! Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this please. -3x - 5y = 61 7x - 5

Algebra ->  Linear-equations -> SOLUTION: I need hep please! Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this please. -3x - 5y = 61 7x - 5      Log On


   

Question 615086: I need hep please! Solve using the elimination method. Show your work. If the system has no solution or an infinite number of solutions, state this please.
-3x - 5y = 61
7x - 5y = -9
Found 3 solutions by stanbon, scott8148, josmiceli:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
-3x - 5y = 61
7x - 5y = -9
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Subtract to get:
10x = -70
x = -7
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Solve for "y":
7x - 5y = -9
7*-7 - 5y = -9
-49 - 5y = -9
5y = -49+9
5y = -40
y = -8
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Solution: (-7.-8)
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Cheers,
Stan H.
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Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
subtracting the equations (to eliminate the y-terms) ___ -10x = 70

solve for x, then substitute back to find y

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +-3x+-+5y+=+61
(2) +7x+-+5y+=+-9+
Multiply both sides of (2) by +-1+
and add the equations
(1) +-3x+-+5y+=+61
(2) +-7x+%2B+5y+=+9+
+-10x+=+70+
Divide both sides by +-10+
+x+=+-7+
Plug this result back into either equation
(2) +7%2A%28-7%29+-+5y+=+-9+
(2) +-49+-5y+=+-9+
Multiply both sides by +-1+
(2) +49+%2B+5y+=+9+
(2) +5y+=+-49+%2B+9+
(2) +5y+=+-40+
(2) +y+=+-8+
The solution is (-7,-8)