I can make it real simple for you. Imagine a triangle, the shadow at point A comes in at a 90 degree angle, while the shadow at point B comes in at a 45 degree angle. Then we know that the angle at point C in the triangle is 45 degree. If the distance between point A and B is 4000 miles, then the distance between point A and C will also be 4000 miles.
I can make it real simple for you. Imagine a triangle, the shadow at point A comes in at a 90 degree angle, while the shadow at point B comes in at a 45 degree angle. Then we know that the angle at point C in the triangle is 45 degree. If the distance between point A and B is 4000 miles, then the distance between point A and C will also be 4000 miles.
pythagoras rule for triangles
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