Question

An 8.5-meter ladder is leaning against a vertical wall. How many meters is its base from the wall if the ladder reaches 7.5 meters up the wall?

Answer 1

Answer:

  4 m

Step-by-step explanation:

The geometry is that of a right triangle with hypotenuse 8.5 m and one side of length 7.5 m. If "b" represents the distance from the base of the ladder to the wall, the Pythagorean theorem tells us ...

  b² + 7.5² = 8.5²

  b² + 56.25 = 72.25

  b² = 16 . . . . . . . . . . . . . subtract 56.25

  b = 4 . . . . meters . . . (take the square root)

The base of the ladder is 4 m from the wall.

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You may recognize this as the 8-15-17 Pythagorean triple, scaled by 1/2.