Answer :
Step 1) rearrange: x= 12-2y
Step 2) sub x= 12-2y into 3x-10y=0
Step 3) solve
3(12-2y) -10y =0
y=2.25
Step 4) sub y=2.25 into x=12-2y
X=7.5
Step 2) sub x= 12-2y into 3x-10y=0
Step 3) solve
3(12-2y) -10y =0
y=2.25
Step 4) sub y=2.25 into x=12-2y
X=7.5