SOLUTION: Use substitution to solve the system. x-2y=11 2x+5y=-23 x= y=

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Question 1203930: Use substitution to solve the system.
x-2y=11
2x+5y=-23
x=
y=
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
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Use substitution to solve the system.
x-2y=11
2x+5y=-23
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2%282y%2B11%29%2B5y=-23---------this is the most obvious substitution.

Answer by ikleyn(52879) About Me  (Show Source):
You can put this solution on YOUR website!
Use substitution to solve the system.
x - 2y = 11
2x + 5y = -23
~~~~~~~~~~~~~~~~~~~ 

From the first equation, express  x = 2y + 11  and substitute it into the second equatio to get

    2*(2y + 11) + 5y = -23.


Simplify and find y

    4y + 22 + 5y = -23

    9y = -23 - 22

    9y = -45

     y = -45/9 = -5

     x = 2*(-5) + 11 = -10 + 11 = 1.


ANSWER.  x = 1;  y = -5.

Solved.