Question

A ladder 30 feet long leans against a vertical wall, with it's foot 5 feet from the base of the wall. At what distance from the ground does the top of the ladder touch the wall?

Answer 1

We have this right triangle

Answer 2

so use the pythagorean theorem to solve for x

a^2 + b^2 = c^2

x^2 + 5^2 = 30^2

x^2 + 25 = 900

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x = ??