Answer:
Okay, here's the method I'm going to use.
If you drive north 6 miles, and then drive east 19 miles, you are technically making a triangle.
19 miles
l_______________
6 milesl
l
You are just missing the last side of the triangle: the straight line stretching from across your starting point to the ending point. You can find this by using the Pythagorean theorem.
a^2 + b^2 = c^2
6^2 + 19^2 = c^2
36 + 361 = c
397 = c
= 19.924859
Rounded to the nearest tenth, your answer is
19.9 miles
This 3D solid is a strange sideways bowl shape. Each cross section is a ring to show the empty space.
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Explanation:
Check out the diagram below. The graph was created with GeoGebra. We have y = x^2 in red and x = y^2 in blue.
The gray region is the region between the two curves. We spin this gray region around the horizontal green line y = 1 to generate the answer mentioned above.
Note how (1,1) is a fixed point that does not move as this is on the line y = 1. Every other point moves to sweep through 3D space to create the solid figure. One way you can think of it is to think of propeller blades. Or you can think of a revolving door (the door is "flat" so to speak, but it sweeps out a 3D solid cylinder).
