Learning How to Use the Prime G2 - Hallway Pole Problem - In Three Parts

[jte]

(09-02-2019 11:32 PM)jlind Wrote:  ⋮
From this we can readily deduce:
a = x + 5.
Since the larger and smaller triangles are similar, the ratios of their similar sides are equal:
b/a = 10/x, the most relevant ratio to setting up the equation.
b = 10*a/x
b = 10*(x+5)/x, by substitution
b = 10 + 50/x, simplifying the equation

From the Pythagorean Theorem:
c^2 = a^2 + b^2
c^2 = (x+5)^2 + (10 + 50/x)^2
⋮

Nice post!

At the clipped point, once one is down to an equation involving two variables, one could also try using the Advanced Graphing app. Here’s the equation, entered: (with “X” and “Y” used for “x” and “c”)



After going to the Plot view, one can then select PoI / Vertical Extrema from the Trace menu, as shown:



If one has the cursor close to the desired extremum before setting the tracing mode, the cursor should settle on the desired extremum, as shown: (otherwise, one might have to pan / zoom / tap to get the cursor on the desired extremum)