Question 850623
Rearrange:
 6000x - y = 500
-9000x - y = 950
Subtract bottom from top
15000x = -450
Divide both sides by 15000
x = -450/15000 
x = - 0.03
Substitute x = -0.03 into
6000x - y = 500
(6000*-0.03) - y = 500
-180 - y = 500
-y = 500 + 180
-y = 680
 y = -680
x = -0.03 and y = -680
Hope this helps.
:-)