SOLUTION: good evening, I am not sure if this is where I need to ask the question on solving system of equations using substitution (algebraically) but it is worth a try. we have a problem

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Question 932328: good evening,
I am not sure if this is where I need to ask the question on solving system of equations using substitution (algebraically) but it is worth a try.
we have a problem 7x-3y=23
x +2y=13
we can't seem to figure out how you would solve this one. can you help with steps so we can understand
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
a problem
7x - 3y = 23
x + 2y = 13
Arrange the 2nd equation for substitution in the 1st equation
subtract 2x from both sides
x = -2y + 13
:
Replace x with (-2y+13) in the first equation
7(-2y+13) - 3y = 23
-14y + 91 - 3y = 23
-17y = 23 - 91
-17y = -68
y = -68/-17
y = +4
Find x
x = -2(4) + 13
x = 5
:
;
Check these solutions in the 1st equation 7x -3y - 23
7(5) - 3(4) = 23
35 - 12 = 23