A 10-foot ladder leans against a wall. It hits the wall 9 feet up. How far is the base of the ladder from the wall? Apply the Pythagorean Theorem to this problem
triangle
side S1 = 9 feet
hypotenuse H = 10 feet
side S2 - X = ?
the Pythagorean Theorem
H x H = S1 x S1 + S2 x S2 = S1 x S1 + X x X
X x X = H x H - S1 x S1 = 10 x 10 - 9 x 9 = 100 - 91 = 9
X x X = 9
X = 3
How far is the base of the ladder from the wall? 3 feet
check:
H x H = S1 x S1 + X x X
10 x 10 = 9 x 9 + 3 x 3
100 = 91 +9 = 100