Answer:
(-1,4)
x=-1,y=4
Step-by-step explanation:
To solve by elimination, add the two equations together to eliminate y.
5x-4y=-21
-2x+4y=18
-----------------
3x = -3
Divide by 3
3x/3 = -3/3
x=-1
Now we still need to find y
-2x + 4y = 18
-2(-1) +4y =18
2+4y =18
Subtract 2 from each side
-2+2 + 4y = 18-2
4y = 16
Divide by 4
4y/4 = 16/4
y =4