Solving Linear Equations

Linear Equations

Review

Finding slope from ....

• a graph

• a table

• two points

Multiple Choice

What is the slope of the line?

• m = 3/4

• m = 4/3

• m = -3/4

• m = -4/3

Multiple Choice

Find the slope

• 4/5

• 5/4

• -5/4

• -4/5

Multiple Choice

What is the slope?

• 2/3

• 3/2

• -7

• -5

Find the slope between two points

Multiple Choice

Find the slope of a line that passes through the given points:

(5,1) and (8,3)

• $$\frac{2}{3}$$

• $$\frac{-2}{3}$$

• $$\frac{3}{-2}$$

• $$\frac{3}{2}$$

Multiple Choice

Find the slope of the line that passes through:
(5, -10) and (5, -4)

• undefined
• 0
• - 14/10
• 10/14

Writing Equations in Slope Intercept Form

Multiple Choice

Given that the slope is 2/3 and the y intercept is -3 what is the equation of the line?

• y = 2/3x - 3

• y = 2/3x + 3

• y = -2/3x - 3

• y = -2/3x + 3

Multiple Choice

Which equation is being represented by this line?

• y = -x + 2

• y = 1/2x + 2

• y = 3x -4

• y = -3x +2

Multiple Choice

What is the equation of the graph?

• y = -5

• y = 5

• x = -5

• x = 5

Writing linear equation when you have...

• point and slope

• two points

Multiple Choice

What is the equation of the line that goes through the points (2, 9) and (3, 1) ?

• y= 8x - 5

• y= -8x + 25

• y= (1/8)x - 2

• y= (-1/8)x + 1

Multiple Choice

What is an equation of line that is perpendicular to the line y = -3x + 5?

• $$y\ =\ -3x\ +\ 7$$
  

• $$y=\frac{1}{3}x\ +2$$

• $$y\ =\frac{2}{3}x\ -3$$

I can represent a linear function with an equation, table, and graph.

​

​Modeling Linear Functions

EXAMPLE 1

Layla earns $400 per week plus $15 per customer she signs up. Let "C" represent the number of customers. Write an expression to show how much she earns in a week.


Layla automatically earns $400 that week (this is her constant)
She earns $15 per customer (15 times the number of customers)

Expression: 15c + 400

Therefore is she signs 3 customers, we can easily plug that in for the value of c.

Modeling Expressions

Real world problems

Example

Jordan has 3 fewer Australian t-shirts than Ted

Jordan's amount of tshirts can be described as 

t - 3 with t standing for the amount that Ted has.

Multiple Choice

A camp charges families a fee of $625 per month for one child and a certain amount more per month for each additional child. Use the graph to write an equation in slope-intercept form to represent the amount a family with x additional children would pay.

• y = 625x + 225
• y = 225x 
• y = 225x + 625
• y =  625

REVIEW

Multiple Choice

Which of the following situations could be descried by the equation y= -25x + 120

• There are 120 people in the football stadium, and 25 more are entering each hour.
• A plumber charges $25 for a house call and $120 per hour.
• A teacher has 120 students. Her third period has 25 students
• There are 120 gallons of water in a tank. It releases water at a rate of 25 gallons per minute

EXAMPLE 1

Layla earns $400 per week plus $15 per customer she signs up. Let "C" represent the number of customers. Write an expression to show how much she earns in a week.


Layla automatically earns $400 that week (this is her constant)
She earns $15 per customer (15 times the number of customers)

Expression: 15c + 400

Therefore is she signs 3 customers, we can easily plug that in for the value of c.

Multiple Choice

The Roaming Cell Phone Company charges $15.00 per month plus $0.20 per minute of airtime usage.  If Juanita uses x minutes of airtime, what is an equation that can be used to determine her monthly cell phone bill (C)?

• C = 15 + 0.20x
• C =15 (0.20x)
• C = 15 + x + 0.20
• C = 0.20 + 15x

Example 2

Jessica babysits for $10 per hour


Jessica's rate can be described as 10h

Multiple Choice

Which equation would describe "two times a number plus five equals 15"?

• x + 5 = 15
• 2x + 5=15
• x + 2(5) = 15
• 2(x + 5) = 15

Example

Jordan has 3 fewer UK tshirts than Ted

Jordan's amount of tshirts can be described as 

t - 3 with t standing for the amount that Ted has.

Multiple Choice

A T-shirt design company charges your team an initial fee of $25 to create the team's design. Each t-shirt printed with your design costs an additional $8. The equation for this situation is y = 8x + 25. Interpret the y-intercept in context.

• The additional fee of $8.

• The initial fee of $25.

• The additional fee of $25.

• The initial fee of $8.

Multiple Choice

A Great Dane is 40 times the size of a mini poodle. Write an expression to describe this

• p + 40

• 40p

• 40/p

• d - 40

Poll

How well do you think you know this unit?

• I aced this Quizizz lesson!

• I just need a tiny bit more practice!

• Still no clue what's going on!

Multiple Choice

Your age 12 years from now.

• 12y

• y + 12

• y - 12

• y/12

Multiple Choice

TJ has 6 more than triple the amount of cupcakes that Carter has.

• c + 6

• 3c + 6

• 18c

• 3c - 6

Multiple Choice

Mason has 2 more than 1/2 as many legos as Chase.

• c + 2

• c + 1/2 + 2

• 1/2c + 2

• 1/2c - 2

Multiple Choice

Chelsee has 12 less pineapples than Sam.

• s - 12

• 12 - s

• s/12

• 12/s