SOLUTION: solving by elimination method. 5x+5y=-11 7x-3y=13

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Question 442559: solving by elimination method. 5x+5y=-11
7x-3y=13

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
solving by elimination method.
5x+5y=-11
7x-3y=13
:
Multiply the 1st equation by 3, multiply the 2nd equation by 5, results:
15x + 15y = -33
35x - 15y = 65
-----------------addition eliminates y, find x
50x = 32
x = 32%2F50
simplify, divide by 2
x = 16%2F25 or x = .64
:
Find y using the 1st equation:
5(16%2F25) + 5y = -11
16%2F5 + 5y = -11
same as
3.2 + 5y = -11
5y = -11 - 3.2
5y = -14.2
y = -14.2%2F5
y = -2.84
:
:
Check solutions in the 2nd original equation:
7x - 3y = 13
7(.64) - 3(-2.84) = 13
4.48 + 8.52 = 13
13 = 13; confirms our solutions