Answer:

Step-by-step explanation:
Given
x 2 4 6 8
y 1 -2 -5 -8
Required
Determine the slope
First, pick any two corresponding x and y values.


The slope (m) is then calculated using:

Substitute in, the x and y values




Divide numerator and denominator by 3


<em>Hence, the slope is -3/2</em>
other factor for given polynomial is y+1
Markup = $4
b) markup as a percentage of cost is 33.3%
Step-by-step explanation:
Markup
markup = selling price - cost
= $13 - 9
... markup = $3
Markup as a Percentage of Cost
To find the percent markup, divide the markup by the reference value and multiply the ratio by 100%. The reference value for markup is usually cost price, but sometimes may be selling price.
... markup / cost × 100% = 3/9×100% = 33 1/3% ≈ 33.3%