1 / 32

# Lesson Menu - PowerPoint PPT Presentation

Lesson Menu. Main Idea and New Vocabulary NGSSS Example 1: Find Slopes and y -intercepts Example 2: Find Slopes and y -intercepts Example 3: Write an Equation in Slope-Intercept Form Example 4: Write an Equation in Slope-Intercept Form Example 5: Graph Using Slope-Intercept Form

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about ' Lesson Menu' - uma-garza

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Main Idea and New Vocabulary

NGSSS

Example 1: Find Slopes and y-intercepts

Example 2: Find Slopes and y-intercepts

Example 3: Write an Equation in Slope-Intercept Form

Example 4: Write an Equation in Slope-Intercept Form

Example 5: Graph Using Slope-Intercept Form

Example 6: Graph an Equation to Solve Problems

Example 7: Graph an Equation to Solve Problems

Five-Minute Check

• slope-intercept form

• y-intercept

Main Idea/Vocabulary

MA.8.A.1.2 Interpret the slope and the x- and y-intercepts when graphing a linear equation for a real-world problem.

NGSSS

State the slope and y-intercept of the graph of y = x – 5.

Write the equation in the form y = mx + b.

Answer: The slope of the graph is , and the y-intercept is −5.

Find Slopes and y-intercepts

Example 1

State the slope and y-intercept of the graph of .

A.slope: ; y-intercept: 1

B.slope: ; y-intercept: 1

C.slope: 1; y-intercept:

D.slope: 1; y-intercept:

Example 1 CYP

Find Slopes and y-intercepts

State the slope and y-intercept of the graph of 2x + y = 8.

2x + y = 8 Write the original equation.

2x –2x+ y = 8 – 2xSubtract 2x from each side.

y = 8 − 2x Simplify.

y = −2x + 8Write the equation in the form y = mx + b.

y = mx + bm = –2, b = 8

Answer: The slope of the graph is –2 and the y-intercept is 8.

Example 2

State the slope and y-intercept of the graph of y – 4x = 10.

A. slope: –4; y-intercept: 10

B. slope: 4; y-intercept: 10

C. slope: 10; y-intercept: –4

D. slope: 10; y-intercept: 4

Example 2 CYP

Write an equation of a line in slope-intercept form with a slope of 2 and a y-intercept of –8.

y = mx + bSlope-intercept form

y = 2x +(–8)Replace m with 2 and b with –8.

y = 2x – 8Simplify.

Answer: y = 2x – 8

Example 3

Write an equation of a line in slope-intercept form with a slope of – and a y-intercept of 6.

A.y = – x – 6

B.y = – x + 6

C.y = x + 6

D.y = 6x –

Example 3 CYP

So, the slope is – . slope of

Write an Equation in Slope-Intercept Form

Write an equation in slope-intercept form for the graph shown.

The y-intercept is 1. From (0, 1), you move up 2 units and left 3 units to another point on the line.

Example 4

y slope of = –x + 1Replace m with – and b with 1.

y = – x + 1

Answer: y = – x + 1

Write an Equation in Slope-Intercept Form

y = mx + bSlope-intercept form

Example 4

A. slope of y = –3x – 2

B.y = 3x – 2

C.y = – x – 1

D.y = x – 1

Write an equation in slope-intercept form for the graph shown.

Example 4 CYP

Graph using the slope and slope of y-intercept.

y = x + 2 slope = , y-intercept = 2

Graph Using Slope-Intercept Form

Step 1Find the slope and y-intercept.

Example 5

Graph Using Slope-Intercept Form slope of

Step 2 Graph the y-intercept 2.

Example 5

slope of change in y: up 2 units←change in x: right 3 units

m =

Graph Using Slope-Intercept Form

Step 3Use the slope to locate a second point on the line.

Example 5

Graph Using Slope-Intercept Form slope of

Step 4Draw a line through the two points.

Example 5

Graph slope of y = – x + 3 using the slope and y-intercept.

A.B.

C.D.

Example 5 CYP

KAYAK RENTAL A kayak rental pavilion charges \$15.00 per hour and \$2.50 for instruction on how to not fall out of the kayak. The total cost is given by the equation y = 15x + 2.5, where x is the number of hours the kayak is rented. Graph the equation to find the total cost for 2 hours.

y = 15x + 2.5 slope = 15, y-intercept = 2.5

Example 6

Plot the point (0, 2.5).

Locate another point up 15 and right 1.

Draw the line.

The y-coordinate is 32.5 when the x-coordinate is 2, so the total cost for 2 hours is \$32.50.

Answer: The total cost for 2 hours is \$32.50.

Example 6

POTTERY slope of A pottery studio charges \$16 per hour and \$10 for firing fees. The total cost is given by the equation y = 16x + 10, where x is the number of hours a customer uses the studio. Graph the equation to find the total cost for 5 hours.

A.\$26

B.\$80

C. \$90

D.\$100

Example 6 CYP

KAYAK RENTAL A kayak rental pavilion charges \$15.00 per hour and \$2.50 for instruction on how to not fall out of the kayak. The total cost is given by the equation y = 15x + 2.5, where x is the number of hours the kayak is rented. Interpret the slope and the y-intercept.

Example 7

Answer: The slope 15 represents the rate of change or cost per hour. The y-intercept 2.5 is the charge for instruction.

Example 7

POTTERY slope of A pottery studio charges \$16 per hour and \$10 for firing fees. The total cost is given by the equation y = 16x + 10, where x is the number of hours a customer uses the studio. Interpret the slope and the y-intercept.

A.The slope 10 represents the firing fee. The y-intercept 16 is the cost per hour.

B.The slope 10 represents the cost per hour. The y-intercept 16 is the firing fee.

C.The slope 16 represents the firing fee. The y-intercept 10 is the cost per hour.

D.The slope 16 represents the cost per hour. The y-intercept 10 is the firing fee.

Example 7 CYP

A. slope of m = ; b = 1

B.m = 1; b = 2

C.m = 2; b = –

D.m = 2; b = 1

State the slope and the y-intercept for the graph of the equation y = 2x + 1.

Five Minute Check 1

State the slope and the slope of y-intercept for the graph of the equation y = 3x + 2.

A.m = –2; b = 3

B.m = 2; b = 3

C.m = 3; b = –2

D.m = 3; b = 2

Five Minute Check 2

State the slope and the slope of y-intercept for the graph of the equation y = −2x + 4.5.

A.m = −4.5; b = –2

B.m = −2; b = 4.5

C.m = 2; b = 4.5

D.m = 4.5; b = –2

Five Minute Check 3

State the slope and the slope of y-intercept for the graph of the equation 3x − y = 4.

A.m = 3; b = −4

B.m = –3; b = −4

C.m = 3; b = 4

D.m = −4; b = 3

Five Minute Check 4

The total price of apples slope of y at an orchard can be calculated with the equation 1.12x + 5 = y, where x is the number of pounds of apples picked. What does the slope represent?

A.the total price of apples

B.the price of apples per pound

C.the number of apples per pound

D.the number of pounds of apples picked

Five Minute Check 5

A. slope of y = 2x –

B.y = x + 2

C.y = x − 2

D.y = x – 2

What is the equation of the graph?

Five Minute Check 6