Bellwork

Write an equation that satisfies the following criteria Passes through (3,4) and m=3 Passes through (-2,2) & (1,8)

A carnival charges an entrance fee and a ticket fee. One person paid $27.50 and bought 5 tickets, while another paid $45 and bought 12 tickets. How much would 22 tickets cost

Clickers

Bellwork Solution Write an equation that satisfies the following

criteria Passes through (3,4) and m=3

. 3 4

. 4 3

. 3 5

. 3 13

A y x

B y x

C y x

D y x

Bellwork Solution Write an equation that satisfies the following

criteria Passes through (-2,2) & (1,8)

. 2 6

. 2 10

. 6 14

. 2 8

. 2 8

A y x

B y x

C y x

D y x

E y x

b

b

b

bmxy

15

3045

)12(50.245

Bellwork Solution A carnival charges an entrance fee and a ticket

fee. One person paid $27.50 and bought 5 tickets, while another paid $45 and bought 12 tickets. How much would 22 tickets cost?

12

12

xx

yy

7

50.1750.2

70

1555

15)22(50.2

y

y

y

bmxy

512

5.2745

.$50

.$62.50

.$67.50

.$70

A

B

C

D

Write Linear equations in Point-Slope Form

Section 5.3

The Concept

Yesterday we spent learned how to take a point and a slope to write a linear equation

Today we’re going to take a look at a another linear form, that can aid us in our efforts to write linear equations

Point Slope Form

As we’ve already seen, linear equations are often just various rewritten iterations of the same equation

It make sense then that there is a form that exists that combines a point and a slope

This form is cleverly named, Point Slope Form. Today we’re going to talk about Point Slope Form

It’s common form can be seen a

This form is based on the ideas presented by slope intercept form

1 1( )y y m x x

Point Slope Form

Let’s look at how we can take this back to slope intercept form

1 1( )y y m x x

1 1y y mx mx

1 1y mx mx y

y mx b 1 1y mx b

1 1y mx b

y mx b

Point Slope Form

Let’s do an example involving this form Write an equation for a line with slope 2 and passes

through the point (4, -3)

3 2( 4)y x

1 1( )y y m x x 3 2( 4)y x

2( 4) 3y x

Point Slope Form

We can also easily convert this form back to slope-intercept form

3 2( 4)y x

2 11y x 3 2 8y x

On your own

Write an equation for a line with slope 5 and passes through the point (8, -5)

. 8 35

. 5 35

. 8 45

. 5 45

A y x

B y x

C y x

D y x

On your own

Write an equation for a line with slope of ½ and passes through the point (-4, 1)

12

12

12

12

. 1

. 3

. 3

. 1

A y x

B y x

C y x

D y x

PracticeYou are designing a sticker to advertise your band. A

company charges $225 for the first 1000 stickers and $80 for each additional 1000 stickers. Write an equation that gives the total cost (in dollars) of stickers as a function of the number (in thousands) of stickers ordered.

. 80( 1) 225

. 80 1225

. 80 1000

. 80(225 1000)

A y x

B y x

C y x

D y x

Homework

5.3 Exercises

1, 2, 7-19 odd, 45-52 even

PracticeExample 5, page 295

. , 100 150

. , 50 50

. ,

. ,

AYes C n

B Yes C n

C No it changes tomucheachtime

D No the linewould becurved

Most Important Points

Point-Slope Form Changing between forms