Here is my answer. In this problem, you need to use the similarity of triangles. I hope this is helpful.
Power rule
y^3(2)
y^6y^7
product rule, add them
y^13
Constant of Variation has this formula for Direct Variation.
y = kx
Where y = cost in dollars; x = length in meters; k = constant
We will use the formula for direct variation because the problem states that the cost varies directly to the length.
In the problem we need to get the constant of variation.
k = y/x
k = $4500 / 200 meter
k = $22.50 cost per meter.
A.) The equation relating C and s is:
k = C/s
* i just substituted C for y and s for x.
B.) The constant of variation represents the additional cost that the company will pay for every meter in length they add. which is $22.50 per meter.
C.) y = kx ; substitute C and s to y and x respectively;
C = ks
C = $22.50 * 700 m
C = $15,750
