WARM UP

1. Which ordered pair could be the coordinates of the y-intercept of a

graph?

2. Solve for :

3. Solve for :

4. Find when :

5. Find when :

LESSON 49, WRITING EQUATIONS IN SLOPE-INTERCEPT FORMFunctions, Expressions and Equations

SLOPE-INTERCEPT FORM

• Slope intercept form can be used to quickly and easily graph lines.

• Slope intercept form tells us the slope and the y-intercept for a line.

• Using this information, we can plot the intercept and use the slope to find

another point.

• Slope-intercept form: , where the value of is the slope of the line and

the value of is the -intercept.

EXAMPLE

Identify the slope and -intercept of the line .

EXAMPLE

What is the equation of the graphed line?

EXAMPLE

The formula for converting from Celsius to Fahrenheit is , where is the temperature in degrees Celsius and is the temperature in degrees Fahrenheit. Identify the slope and -intercept of the equation and then graph it.

EXAMPLE

The directions on a box of frozen biscuits state to cook one biscuit for 90 seconds on high and to add 15 seconds of cooking time for each additional biscuit.

a. Write a linear equation in slope-intercept form to represent the situation. Identify what the variables and represent.

b. What is the -intercept of the graph? Does it have any meaning? Why or why not?

HOMEWORK QUESTIONS

CORRECTING HOMEWORK

• Be kind.

• Be diligent.

• Hold questions until the end.

• Make sure the paper in front of you is in black ink or pencil.

• Make sure the paper in front of you is complete and that work has been shown.

• Starting today, the score sheets will be filled out by the person correcting.

HOMEWORK

• 1st and 2nd hour: Lesson 49 #1-30

• 3rd hour: Lesson 49 #1-15

• Don’t forget there is a test tomorrow!