Question

What is the y-intercept of:
1: slope=2, passes through (-5,-17)
2: slope=-5, passes through (2,-20)
3: slope=1/2, passes through (-2,-1)

Answer 1

y intercept;when x=0

Answer 2

just plug them each into y=mx+b

Answer 3

and solve for b in each

Answer 4

y-y1=m(x-x1)
y-(-17)=2(x-(-5)
y+17=2x+10
y=2x+10-17
x=0 at the y intercept
y=-7