http://www.chhsweb.ca/docs/homework/Unit%201%20Review1.pdf
Can someone tell me how to do 28 please
Can someone tell me how to do 28 please
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Take the bottom cone they are talking about, and split it into two right triangles by drawing a vertical line from the midpoint of the upper base of the cone, down to the bottom point of the cone. Now you know one side of the triangle is 8ft, and it happens to be the side adjacent to the given angle. Recall that the tan(x) is opposite / adjacent. The line you drew ends up being the opposite side of the triangle.
tan(40) = depth / 8
8 * tan(40) = answer to part A.
For part B, you can say the radius of the cone is 8ft, and the height of the cone is the answer to part A. plug those two into the formula for volume of a cone.
For part C, you're given the volume of the bottom cone plus the middle cylinder, and asked to find the height of the cylinder. Subtract the volume calculated in part B from the given volume (4042 ft^3) to get the volume of the cylinder. Then set that use the formula for volume of a cylinder to solve for the height of the cylinder.
tan(40) = depth / 8
8 * tan(40) = answer to part A.
For part B, you can say the radius of the cone is 8ft, and the height of the cone is the answer to part A. plug those two into the formula for volume of a cone.
For part C, you're given the volume of the bottom cone plus the middle cylinder, and asked to find the height of the cylinder. Subtract the volume calculated in part B from the given volume (4042 ft^3) to get the volume of the cylinder. Then set that use the formula for volume of a cylinder to solve for the height of the cylinder.
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Make a guess.