SOLUTION: 2x + 9y = 29 -5x + y = 45

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Question 1041322: 2x + 9y = 29
-5x + y = 45
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
system%285%282x%2B9y%29=5%2A29%2C2%28-5x%2By%29=2%2A45%29

system%2810x%2B45y=145%2C-10x%2B2y=90%29

%2810x%2B45y%29%2B%28-10x%2B2y%29=145%2B90

You can continue the necessary following steps.


-
y=5

Answer by ikleyn(52800) About Me  (Show Source):
You can put this solution on YOUR website!
.
2x + 9y = 29
-5x + y = 45
~~~~~~~~~~~~~~~~~~~~~~~ 

2x + 9y = 29,           (1)
-5x + y = 45            (2)

I will show you how to solve it by applying the Substitution method.

From the equation (2), express "y" via x  y = 45 + 5x. 
Next substitute this expression for "y" into equation (1). Then (1) takes the form

2x + 9*(45+5x) = 29.    (3)

Now simplify and solve it:

2x + 405 + 45x = 29  --->  47x = 29 - 405  --->  47x = -376  --->  x = -376%2F47 = -8.

Thus we got x = -8.  Then from (2) y = 45 + 5x = 45 + 5*(-8) = 5.

Please check yourself the answer.

Answer.  x = -8, y = 5.

On solution systems of two equations in two unknowns see the lessons
    - Solution of a linear system of two equations in two unknowns by the Substitution method
    - Solution of a linear system of two equations in two unknowns by the Elimination method
    - Solution of a linear system of two equations in two unknowns using determinant
    - Geometric interpretation of a linear system of two equations in two unknowns
    - Solving word problems using linear systems of two equations in two unknowns
in this site.