-4x+y=6
-5x+y=21
Step 1: Pick an equation & solve for x
-4x+y=6
-y -y
-4x=6-y
x=(6-y)/4
Step 2: Plug in the equation you just got into the x in the second equation
-5((6-y)/4)=21
Step 3: Solve for y
(-30+y)/4=21
-30+y=84
+30 +30
y= 114
Step 4: Plug in the y into the first equation and solve for x
-4x+114=6
-114 -114
-4x=-108
x= 27
Answer: x=27 & y=114
