connir
Nov 18, 2010, 09:13 AM
9x - 7y = 120.5
-36x + 28y = -482
 
(2)       -2x -  8y = 22
              -6x - y = 20
Unknown008
Nov 19, 2010, 05:42 AM
9x - 7y = 120.5
-36x + 28y = -482
 
The second equation can be simplified. Divide it by 4:
 
-9x + 7y = -120.5
 
Well... since both equations are the same, they meet from negative infinity to positive infinity.
 
-2x - 8y = 22
-6x - y = 20
 
Simplify the first equation by dividing it by 2:
-x - 4y = 11
 
Multiply the second equation by 4:
-24x - 4y = 80
 
Now, subtract one equation from the other. Can you do this?
 
 
   -  x - 4y = 11
-  -24x - 4y = 80