The bottom of a ladder must be placed 7 feet from a wall. The ladder is 17 feet long. To the nearest tenth of a foot, how far above the ground does the ladder touch the wall?

Answer 1

This situation can be modeled as a right triangle with a base leg of 7 feet and an hypotenuse with a length of 17 feet. The height that the ladder touches the wall above the ground would be the missing leg or x.

Then using the Pythagorean theorem: 7² + x² = 17²

49 + x² = 289

49 + x² - 49 = 289 - 49

x² = 240

x = 15.5 feet

The ladder will touch the wall 15.5 feet above the ground.