I think there is more to the question, but the equation to solve for the number of months until Rita has enough money to put a down payment for a condominium is 15,000=8,000+850X
To calculate distance between two points we use the distance formula sqrt((x2−x1)^2+(y2−y1)^2).
To start, we find the square of the distance between x1 and x2 and y1 and y2. The distance between x1 and x2, or 1 and 3, is 2. The distance between y1 and y2, or 3 and -4, is 7.
Now we square 2 and 7 and add them together to get 4 + 49 = 53.
The last thing we do to find the distance is take the square root of 53. 53 is not a perfect square and is also a prime number so our answer in simplest form is still sqrt53.<span />
The parametric equations for x and y describe a circle of radius 10 m, so the length of the base of the fence is the length of the circumference of a circle of radius 10 m. The formula for that circumference (C) is ...
... C = 2πr
... C = 2π·(10 m) = 20π m
The height as a function of angle (t) is found by substituting for x and y.
... h(t) = h(x(t), y(t)) = 4 + 0.01·((10cos(t))²-)10sin(t))²) = 4+cos(2t)
The average value of this over the range 0 ≤ t ≤ 2π is 4, since the cosine function has two full cycles in that range, and its average value over a cycle is zero.
Thus, the area of one side of the fence is that of a rectangle 20π m long and 4 m wide. That will be
... (20π m)·(4 m) = 80π m²
The amount of paint required to cover both sides of the fence is
... 2×(80π m²)×(1 L)/(10 m²) = 16π L ≈ 50.3 L
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You can work out the integral for area as a function of t. When you do, you will find it gives this same result.
18/9, or 2/1. OR you can write that as 2
