Eight algebra questions (explanations would be appreciated):

use substitution to solve the following:

1)
y=x²
y=x+2

2)
y=x²+3
y=4x

3)
x²+4y=1
y=x+1

4)
x²-3y=-2
y=4+x

5)
x²-2y=-4
y=6-x

6)
x²+4y=9
y=x-3

7)
x²+5y=16
y+x=2

8)
y=x²-6x
3x-y=-10