SOLUTION: Solve by the substitution method. What is the solution of the system? 7x+3y= -35 -7x+y=63

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Question 418186: Solve by the substitution method. What is the solution of the system?
7x+3y= -35
-7x+y=63
Found 2 solutions by sudhanshu_kmr, ewatrrr:
Answer by sudhanshu_kmr(1152) About Me  (Show Source):
You can put this solution on YOUR website!

solution: x = -8, y = 7
using 2nd equation we get y = 63 + 7x
put the y = 63 + 7x on first equation and find the value of x.
then after value of y.



Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

-7x+y=63 OR y = 7x+63

7x+3y= -35

7x + 3(7x+63) = -35

     28x = -224

       x = -8 and y = 7  (-56+63)



CHECKING our Answer***

using elimination method

 7x+3y= -35

-7x+ y=63

    4y = 28

     y = 7 and x = -56/7 = -8 (using 1st EQ)