(1,-1) and (3,5)
Find slope first
y=mx+b
slope is also m
b is y-intercept
slope = y2-y1/x2-x1
x1=1
x2=3
y1=-1
y2=5
5-(-1)/(3)-(1)
6/2=3
y=3x+b
use (1,-1) into y=3x+b ( using substitution method)
-1=3(1)+b
-1=3+b
Move 3 to the other side
Sign changes from +3 to -3
-1-3+3-3+b
b=-4
Answer: C.) Y = 3x-4
