# Find the Slope and Y-Intercept (-1,3) , (2,9)

(-1,3) , (2,9)
Find the value of the slope.
Slope is equal to the change in y over the change in x, or rise over run.
m=change in ychange in x
The change in x is equal to the difference in x-coordinates (also called run), and the change in y is equal to the difference in y-coordinates (also called rise).
m=y2-y1x2-x1
Substitute in the values of x and y into the equation to find the slope.
m=9-(3)2-(-1)
Simplify.
Simplify the numerator.
Multiply -1 by 3.
m=9-32-(-1)
Subtract 3 from 9.
m=62-(-1)
m=62-(-1)
Simplify the denominator.
Multiply -1 by -1.
m=62+1
m=63
m=63
Divide 6 by 3.
m=2
m=2
m=2
Find the value of the y-intercept.
Substitute the value of m into the slope-intercept form of the equation, y=mx+b.
y=(2)⋅x+b
Substitute the value of x into the slope-intercept form of the equation, y=mx+b.
y=(2)⋅(-1)+b
Substitute the value of y into the slope-intercept form of the equation, y=mx+b.
3=(2)⋅(-1)+b
Rewrite the equation as (2)⋅(-1)+b=3.
(2)⋅(-1)+b=3
Multiply 2 by -1.
-2+b=3
Move all terms not containing b to the right side of the equation.
Add 2 to both sides of the equation.
b=3+2