If a quadrilateral has four congruent sides and four right angles, then it's a square, and also If two consecutive sides of a rectangle are congruent, then it's a square.
Glad I could help, Have a great day!
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.
I hope this helps you
h=S-2pi.r^2/2pi.r
This scenario can be expressed by the equation 6x + 2x = 80
first, add 6x and 2x because they are like terms
you are left with 8x = 80
divide both sides and we know that x = 10.
so, put 10 back into the original equation:
6(10) + 2(10) = 8
There are 60 girls and 20 boys :)