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?

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