1 is the height of one side, forming a right triangle. The hypotenuse of a right triangle is 6, the short right side is 3, and the other side is 3 times the root sign, which is the height. The area is the base times the height times half, 3 times the root number 3 times 6 times half = 9 times the root number 3.

2 S= 12*5* half = 13 (hypotenuse) * height * half solution height =60/ 13.

According to Pythagorean Theorems A and B, if one is 6 and the other is 8, then S=24.

4 Pythagorean theorem shows that the height of the wall is 2.5 square +0.7 square and then the root sign =2.4.

The height against the wall after sliding is 2.4-0.4=2. If the ladder is 2.5, it is 1.2.