SOLUTION: Please help me with solving this problem. I am confused because it started out with equal first:8x = 9 -5y 8x - 3y = -31 Do I turn it around to solve like this

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Please help me with solving this problem. I am confused because it started out with equal first:8x = 9 -5y 8x - 3y = -31 Do I turn it around to solve like this      Log On


   

Question 256661: Please help me with solving this problem. I am confused because it started out with equal first:8x = 9 -5y
8x - 3y = -31
Do I turn it around to solve like this: 9 - 5y = 8x
8x -3y = -31
8x-8x=0
5y - 3y = 2y
80 - 31= 49
8x = 0

8x - 3y = -31
I am sorry, I am stuck. Thank you for your help.
Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
I would use simple substitituon for this one. You are given
8x+=+9+-5y
You are then told
+8x+-+3y+=+-31
So take the value for 8x in the first equation and substitute that into the second like this
+8x+-+3y+=+-31
%289-5y%29+-+3y+=+-31
9+-+5y+-+3y+=+-31
-8y+=+-40
y=5
So, if y=5, you can find x
8x+=+9+-+5y
8x+=+9+-+5%2A5
8x+=+9+-+25
8x+=+-16
x+=+-2
So the solution is (-2,5)
You can also graph the two lines and see that the point they intersect is (-2,5)
graph%28400%2C400%2C-10%2C10%2C-10%2C10%2C%289-8x%29%2F5%2C+%288x%2B31%29%2F3%29