Linda found that the cost to get a swimming pool installed in her backyard is a linear function of the pool's area. A swimming pool with an area of 1,500 square feet can be installed for $54,000, whereas the installation of a 700 square foot swimming pool costs $30,000. Make a graph that represents this function and write the equation of the line. Let A represent the pools area and C represent the cost.
Accepted Solution
A:
Answer:T he equation of the line is [tex]C = 30A + 9000[/tex]Step-by-step explanation:If A represents the Area and C represents the cost, then we know that:
For an area [tex]A = 1500[/tex] square feet, the cost is [tex]C = 54000[/tex]
If [tex]A = 700[/tex], then, [tex]C = 30000[/tex]
Since we know that the cost equation is a function of the area it is a linear relationship so we must find the equation of the line
[tex]C = mA + b[/tex]Where:
m is the slope of the line
b is the intersection with the C axis ..
We already have 2 points:
(700, 30000)
(1500, 54000)
With these points we find the slope using the formula:[tex]m = \frac{y_2 -y_1}{x_2-x_1}\\\\m = \frac{54000-30000}{1500-700}\\\\m = 30[/tex]So the equation is:[tex]C = 30A +b[/tex]We find b replacing the point (700, 30000) in the equation[tex]30000 = 30(700) + b\\\\30000 -21000=b[/tex][tex]b = 9000[/tex]So [tex]C = 30A + 9000[/tex]The graph of the linear equation is shown in the attached image