Question

What is 2x+y=8 and x-2y=-1

Answer 1

The solutions of x and y?

2x+y=8...(1)
x-2y=-1...(2)
for (2), x=-1+2y...(3)
sub(3) into(1),
2(-1+2y) +y=8
-2+4y+y=8
5y=10
y=2
sub y=2 into(3)

x=-1+2(2) =3
therefore, x=3,y=2