algebra
posted by Anonymous .
a 17foot ladder leans against a wall. if the ladder is 8 feet from the base of the wall, how far is it from the bottom of the wall to the top of the ladder

15ft
imagine a triangle. The diagonal side is 17 ft. the bottom is 8 ft. Use the pythagorean theorem to find the third side. so
17^2 minus 8^2 = 225. then take the square root of 225, which is 15 
Let c = the length of the ladder. b = the distance from the wall. Use the Pythagorean theorem.
a^2 + b^2 = c^2
a^2 + 8^2 = 17^2
a^2 + 64 = 289
a^2 = 225
a = 15 
my way worked too

Yep. It's always good to show students more than one way to solve a problem.
Btw  I hadn't seen your post when a posted mine. 
*I posted mine.

oh ok :)

A ladder with length 20m. stands vertically against a wall. How much further should the lower end of the end of the ladder be moved so that its upper end descends 4 metre?

My 20 foot ladder was about 8 feet from the wall and by the time my face busted on the rock below I didn't do any measuring.
I drove to the hospital and got many stitches.