Question

A 10-foot ladder is leaning against a wall. The base of the ladder is 2 feet from the base of the building. How far up the building does the ladder fall?

Answer 1

We can see on this graph that the triangle has legs of x and 6 with a hypotenuse of 10 and we can use Pythagoreans theorem to find the unknown side.
Pythagoreans theorem: a^2+b^2=c^2, where a and b are the legs of the triangle and c, is the hypotenuse 

x^2+6^2=10^2 Plugin a=x, b=6, and c=10. Now let us solve for x 

x^2+36=100 Square each individual term 

x^2+=100+36 Subtract 36 from both sides 

x^2=64 Combine like terms 

sqrt(2)=sqrt(64) Take the square root of both sides 

x = 8 Simplify the square root 

So our answer is x = 8 
The ladder touches the 8 feet mark on the wall.