This problem comes from Mind Your Decisions. The problem is to find the length of a side of the blue square.
 |
| The problem square |
 |
| The embellished square |
Having worked on similar problems from Presh, I was familiar with his line of attack, so I stopped the video early on and put together my own drawing which is very similar to the one I stole from the video.
Now we have a bunch of right triangles so we can set up a couple of two-variable equations. You can see them in the video. Mine are virtually identical, but I don't want to type them out. I don't know how to solve these equations, and apparently Presh doesn't either. He turned to Wolfram Math, I turned to Desmos graphing calculator.
 |
| Desmos graph of two equations |
Notice there are two gray dots where the red line intersects the blue line. Before I completed the screen shot Desmos was showing the coordinates of the rightmost intersection to be (1.598, 3.798). Use these numbers as the sides of right triangle a-b-s and the Pythagorean formula tells us the length of the side of the square is 4.120.
In the equations I used in Desmos, I used x for b and y for a.
No comments:
Post a Comment