Comparing Linear Equations

A holiday meal costs $12.50 a person plus a delivery fee of $30.

• y = 30 + 12.5x 

• y = 12.5 + 30

• y = 12.5 + 30x

• y = 30 - 12.5x

Is the function Linear or Nonlinear?

• Linear

• Nonlinear

The cost of Nate’s service is described by y = 4x + 6. The table shows the cost of Beth’s service. Which service is cheaper for renting 9 movies?

• Beth's service is cheaper (Beth charges $42 vs. Nate charges $45)

• Nate’s service is cheaper (Nate charges $42 vs. Beth charges $45) 

• Nate’s service is cheaper (Nate charges $36 vs. Beth charges $45)

• Beth's service is cheaper (Nate charges $45 while she charges $36) 

What is the equation of this line?

• 0

• undefined 

• y = -2

• x = -2

Linear Function, Nonlinear Function, Not a Function?

• Linear Function

• Nonlinear Function

• Not a Function

The cost of Nate’s service is described by y = 4x + 6. The table shows the cost of Beth’s service. Find the equation for Beth's service.  Which service is cheaper for 8 movies in one month?

• Beth's service ($38 vs. $40) is cheaper

• Nate’s service ($42 vs. $44) is cheaper

• Nate’s service ($38 vs. $40) is cheaper

• Beth's service ($42 vs. $44) is cheaper

Find the slope. Simplify, if you can.

• 2

Fill in the missing blanks.

The Slope - ​ (a)   form of an equation is y = ​ ​ (b)   x+​ (c)   where "m" is the ​ (d)   and b is the ​ (e)  

• intercept

• m

• b

• slope

• y-intercept

The graph shows a line with a ​ (a)   slope. The VALUE of the slope is ​ (b)   . The equation of the line is

y = ​ (c)   x - ​ (d)   .

• negative

• -1

• 2

• positive

• 1

• -2

Answer explanation

Lines that go downhill from left to right have a negative slope.

Use rise over run to find the slope.

Negative slope is found by "up and to the left" or "down and to the right".