Question 449477
9x+3y=-30	.............1				
y=20+3x	---------2				
/1=									
y=20+3x					
Plug the value of y in (1)											
9x+3(20+3x)=-30
9x+60+9x=-30			
9x+9x=	-30	-60				
18x=-90								
/18										
x=-5										
Plug the value of x in (1)											
9x+3y=-30					
9*-5+3y=-30				
-45+3y=-30						
3y=15								
/3										
y=5										
(-5,5)