SOLUTION: My question is can you help me solve this equation? This problem is a Substition. x+2y=13 3x-5y=6 I do not understand how to find x and y for this equation. If you could hel

Algebra ->  Expressions-with-variables -> SOLUTION: My question is can you help me solve this equation? This problem is a Substition. x+2y=13 3x-5y=6 I do not understand how to find x and y for this equation. If you could hel      Log On


   



Question 123232: My question is can you help me solve this equation? This problem is a Substition.
x+2y=13
3x-5y=6
I do not understand how to find x and y for this equation. If you could help it would be great. Thank you.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Discussion



To solve a system of linear equations by substitution, you first solve one
of the equations for one of the variables to get an expression for that
variable in terms of the other. Then you substitute this expression into the
second equation giving you a single equation in a single variable that can be
solved by ordinary methods





Solution



x%2B2y=13
3x-5y=6

Solve the first equation for x:
x%2B2y=13
Add -2y to both sides
x=13-2y

Take this expression for x and substitute it into the second equation:
cartoon%283%2Ared%28x%29-5y=6%2C3%2Ared%28%2813-2y%29%29-5y=6%29

Now solve:
3%2813-2y%29-5y=6%29
39-6y-5y=6
-11y=6-39
-11y=-33
y=3

Now that you know the value of y, you can substitute it into either of the
original equations and solve for x
x%2B2%283%29=13
x%2B6=13
x=7

So the solution set for the system is the ordered pair (7,3)





Check Answer



graph%28400%2C400%2C-10%2C10%2C-10%2C10%2C-x%2F2%2B13%2F2%2C3x%2F5-6%2F5%29

Note that the two lines intersect at the point (7,3)