Point Slope Form

Point Slope Form

by Shalynne Orth

point slope form

How to write an equation of a line given 2 points

Point-Slope form: y-y₁=m(x-x₁)

is another way to find the equation of a line given 2 points

Multiple Choice

What is point slope form?

• $$y=mx+b$$  

• $$m=\frac{y_2-y_1}{x_2-x_1}$$  

• $$y-y_1=m\left(x-x_1\right)$$  

• $$y-x=m\left(x_1-y_1\right)$$  

​Write an equation in point-slope form for each line

Multiple Choice

The line with the equation

y + 1 = -3(x - 5),

contains the point (5, -1)

and has a slope of _______.

• -1

• 1

• -3

• 5

Multiple Choice

For the equation
y - 3 = 2(x + 4),
which of the following is true?

• The line has m = 2 passing through the point (4, -3)
• The line has m = 2 passing through the point (3, -4)
• The line has m = 2 passing through the point (-4, 3)
• The line has m = 2 passing through the point (-3, 4)

Multiple Choice

Write an equation in point-slope form for each line.

Slope is 1/3 and (-3, 1) is on the line.

• $$y+3=\frac{1}{3}\left(x-1\right)$$  

• $$y+1=\frac{1}{3}\left(x-3\right)$$  

• $$y-3=\frac{1}{3}\left(x+1\right)$$  

• $$y-1=\frac{1}{3}\left(x+3\right)$$  

Open Ended

Write as many functions as you can that contain this point?

Fill in the Blanks

Multiple Choice

What is the slope of the line through the points (4, 0) and (-1, 10)?

• -10/3

• 3/10

• 2

• -2

Slope of line through (4,0) and (-1,10)

Reduce the slope -8/2 to -4 and use

y-y₁=m(x-x₁)

• Fill in -4 for the slope (m)

• Choose a point to fill in for (x₁ , y₁)

• We will use (4 ,2)

• y-2 = -4 (x-4)

Multiple Choice

Write the equation in point-slope form for the line that contains the points
(-2, -3), (4, 3)

• y - 3 = 1(x - 2)
• y + 3 = 1(x + 2)
• y -3 = -1(x + 2)
• y + 3 = -1(x - 2)

Multiple Choice

Convert the equation of the line

y + 5 = -3(x - 6)

into slope intercept form.

(AKA Solve for Y!)

• y = -3x - 23

• y = -3x - 13

• y = -3x - 11

• y = -3x + 13