Please show the work process so I can learn how to do it Tha

Please show the work process so I can learn how to do it. Thank you so much.

15) When going more than 38 miles per hour, the gas mileage of a certain car fits the model y=43.81-0.395x where x is the speed of the car in miles per hour and y is the miles per gallon of gasoline. Based on this model, at what speed will the car average 15 miles per gallon? (Round to nearest whole number.)

A) 73 miles per hour           B) 149 miles per hour         C) 98 miles per hour           D) 48 miles per hour

16) Find the periodic payment that will amount to the given sum under the given conditions.

S=$22,000, interest is 4% compounded annually, payments made at the end of each year for 5 years.

$4061.80        B) $2068.32          C) $1788.66          D) $1321.68

17. The information in the chart gives the salary of a person for the stated years. Axis with a linear function using the points (124600) and (326800)

Solution

Q15)

Given when speed is greater than 38 miles per hour, then

y = 43.81 - 0.395*x

Now we need to find the speed when y = 15

substituting the values we get

15 = 43.81 - 0.395*x

0.395*x = 28.81

x = 72.93 miles/hr = 73 miles/hr (nearest integer, correct option is option A)

Q17) No chart is given hence can\'t solve the problem, please upload the chart and post a new problem for the same.