An electric company charges a certain rate per kilowatt-hour (kWh) of electricity used and an administrative fee of $3.50. The company charged zhao $63.25 for using 800 kWh of electricity. Zhao uses the equation, 63.25 = 800r + 3.50 to represent the situation. What does the variable r represent in the equation?

Variable represents the slope of the equation.

Step-by-step explanation:

Given that the administrative fees that company charge is $3.50.

Also, the Zhao has a bill of $63.25.

The equation used by Zhao is

We can compare the equation of a line in the slope-intercept form.

We can see the y-intercept is $3.50 that is a fixed cost. And the company charged $63.25 that is the dependent variable.

Also, variable that is the rate per kilowatt-hour (kWh) represents the slope of the equation.

[First one, aka #11] is d

- I made the system

s - 18 = t

12s = 10t + 32

- Because one sport (s) has 18 less than one technology (t), so s - 18 = t. 12 sport (12s) has 32 more than 10 technology (10t) so if you add 32 to technology, you will get sport (12s = 10t + 32 )

[Second one, aka #13] is a

- If a 20-gallon bathtub is draining at a rate of 2.5 gallons, the max will be 20 gallons. Since it is water/etc, you cannot have negative water, so the least amount will be 0. We now have 0 ≤ ? ≤ 20

- What variable do we use? We are talking about gallons, so we will use g (gallons remaining) to get our answer of a, which is  0 ≤ g ≤ 20

Have a nice day!

  I hope this is what you are looking for, but if not - comment! I will edit and update my answer accordingly. (ノ^∇^)

- Heather