Unit 4 Equations to a Line

Hello Class!!! Today we will:

*Attendance(did you do your puzzle piece yet?)

*Review

*Homework Check

Multiple Select

Put a check mark next to all of the equations that are written in Slope-Intercept Form.

• y - 3 = 8(x + 5)

• y = 3x + 5

• y = 10

• 3x + 2y = 17

Slope Intercept Form

y = mx + b

You want and answer in the m & b spots, but it is possible they are zero, therefor it looks like they are not there,

like in y = 3, or y = 2x

Multiple Choice

If the slope is 3, and the y-intercept is 5, which one below is the correct equation?

• y = -3x + 5

• y = -5x + 3

• y = 3x + 5

• y = 5x + 3

Multiple Choice

If the point is (4,7) and the slope is -1, which equation below is an equation to this line in Slope-Intercept Form?

• y = -1x + 3

• y = -1x - 3

• y = -1x + 11

• y = -1x - 11

Standard Form is Ax + By = C

We can change Standard Form into Slope-Intercept by solving for y.

Multiple Select

The Standard Form of a line is -15x + 5y = 10, write it in Slope-Intercept Form

• y = 15x + 2

• y = 3x + 10

• y = 3x - 10

• y = 3x + 2

Slope-Intercept Form from two points

*Find the slope using

 $\frac{y_2-y_1}{x_2-x_1}$  
*Pick one of the points and the slope you just found and plug into 
y = mx+b
*Solve for b; then use the b and m for final equation

Multiple Choice

The two points are (3,5), (2, 2). What is the equation

in Slope-Intercept Form?

• y = -4x + 3

• y = 4x + 3

• y = x

• y = 3x -4

Point - Slope Form is

 $y\ -y_1=\ m\left(x\ -\ x_1\right)$  

 $\left(x_1,\ y_1\right)$  is the point of the line and 'm' is the slope

Multiple Choice

The Point-Slope Form of a line is y + 4 = -2(x - 8).

The x-value in the point is....

• 8

• -8

• 4

• -4

Multiple Choice

The Point-Slope Form of a line is y + 4 = -2(x - 8).

The y-value in the point is....

• 8

• -8

• 4

• -4

Multiple Choice

Write the following equation in Slope-Intercept Form

y - 10 = 2(x-8)

• y = 2x - 6

• y = 2x + 2

• y = 2x - 2

• y = 2x + 6