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View Full Version : Solve using elimination method 9x - 7y =120.5 , -36x 28y = -482


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