Please show your work. I want to actually understand this. thank you kindly :) 6 problems

Solve with substitution

1)
y = 8x - 6
y = 3x - 1

2)
y = 4x + 18
5x - 6y = -13

3)
y = -3x + 6
-9x - 3y = 7

4)
2x - y = -10
y = 2x + 10

5)
y = -7x - 10
-x - 5y = -18

6)
y = x - 1
-x - y = -19