A 10-FOOT LADDER IS PLACED AGAINST A VERTICAL WALL OF A BUILDING, WITH THE BOTTOM OF THE LADDER STANDING ON LEVEL GROUND 6 FEET FROM THE BASE OF THE BUILDING. How HIGH UP THE WALL DOES THE LADDER REACH?

Answer 1

6^2 + h^2 = 10^2

36 + h^2 = 100

h^2 = 64

h = 8

or you can see that this is a 3 - 4 - 5 right triangle

Answer 2

Since this forms a right angle triangle, we can use the Pythagorean Theorem.

a^2 + b^2 = c^2

a^2 + 6^2 = 10^2

a^2 + 36 = 100

a^2 = 64

a = 8