A12 foot ladder is leaning against a building. the ladder makes a 45 degree angle with the building. how far up the building does the ladder reach ?
a. 24√2
b.6√2
c. 6 feet
d.12√2

If the ladder makes a 45 degree angle with the building, then it also makes a 45 degree angle with the ground (45-45-90). The rule for the 45-45-90 is (x, x, xsqrt2).  The sqrt2 is the hypotenuse measure, which is always the longest of the sides in a right triangle.  If the hypotenuse is 12, set up your equation like this:   In order to undo that square root, square both sides, getting   Now divide both sides by 2 to get and take the square root of both sides and simplify.  The square root of 72 simplified is