How do I solve this problem
1 answer:
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Sphere
The radius of the sphere is the only unknown variable need to find the volume of a sphere.
Step-by-step explanation:
Sphere is a geometrical three dimensional round figure with every point on its surface equidistant from its center. It is a three dimensional representation of a circle. A line which connects from the center to the surface is called radius of the sphere.The diameter of the sphere is the longest straight line which passes through the center of the sphere.
The volume of sphere is given by:
Volume of sphere(V) =
where V is the volume of the sphere
r is the radius of the sphere
= 3.14
Hence the only unknown variable to find the volume of a sphere is the radius.
Answer:
3.189 seconds
Step-by-step explanation:
You want f(t) = 0, so ...
0 = -16t^2 +13.4t +120
0 = t^2 -0.8375t -7.5 . . . . divide by -16
0 = (t^2 -0.8375t +0.41875^2) -7.5 -0.41875^2 . . . . complete the square*
0 = (t -0.41875)^2 -7.6753515625 . . . . write as a square
√7.6753515625 = t -0.41875 . . . . . . . . add 7.67... and take positive root
t = 0.41875 +√7.6753515625 ≈ 3.189192 . . . . add 0.41875
It will take the rock about 3.189 seconds to hit the ground.
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* We complete the square by adding the square of half the coefficient of the linear term (= (-0.8375/2)^2) inside parentheses and subtracting the same amount outside parentheses. This gives a form inside parentheses that is ...
(t^2 -2at +a^2) = (t -a)^2
Completing the square is complicated a little bit by a leading coefficient that is not 1. That is why we divided by -16 first.
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<em>Comment on the question</em>
We note that the rock "falls" from the 120 foot high balcony by first traveling upward at a rate of 13.4 feet per second. We also note that the height function is written f(x), but uses t as the variable. That is, it should be f(t) = ...
