
Kenneth S. answered 07/20/16
Tutor
4.8
(62)
Let's cut to the chase: I know this subject & how to teach YOU
1) Make a sketch as described...acute angle up from the horizontal ground to the Sun is 65o. Said angle faces a vertical side, length h, the height of the flagpole. The shadow is the horizontal leg of the triangle. Do you remember your Geometry class?
tan 65 = h/24. Put your calculator into degree mode, find the tangent of 65 degrees, and then your equation can be tweaked to solve for h.
2) Similar advice...make a diagram...
3) Let's make a sketch (diagram) for this, too. This time, the angle A will just be 80o. How long will the side be for the first boat which goes 20 mph for 2 hours? How long will other side be? After appropriate thought, you have the situation called SAS (two sides & included angle). Use the Law of Cosines to calculate the third side.

Kenneth S.
Well, since Iam retired and living in Thailand, I do have some time before leaving for a bridge game this evening.
So take a sheet of paper. Place a point near the left margin; label it A.
Now, act out, on paper, what is happening. Send a line segment from A upward & to the right, ending at point E. This represents 2 hours of travel at a stated constant speed; you will please decide what to label segment AE, in miles.
Back to point A; send a line segment downward & to the right, ending in point F, such that angle EAF measures 9or at least is labeled) 80o. Please decide what to label AF, in miles.
As I stated earlier, you now have a well labeled triangle, EAF. The labeling is characterized as SAS ('side, angle, side') and I urge you to apply the Law of Cosines to this diagram, thus finding the length, in miles, of EA, i.e. how far apart the two boats are after 2 hours of travel as their (different) constant speeds in mi/hr.
Visualization, through an appropriate diagram, is key to numerous trigonometric applications. ALWAYS MAKE A DIAGRAM & THINK ABOUT IT.
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07/21/16

Kenneth S.
THERE'S A MINOR TYPO in my comment: 9or... should be (or...
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07/21/16
Hannah L.
07/20/16