A 28 -ft ladder leans against a building so that the angle between the ground and the ladder is 79 ∘ .

Question

A -ft ladder leans against a building so that the angle between the ground and the ladder is .

How high does the ladder reach on the building? _____ ft

Answer 1

With the details given, we can picture a right triangle with a hypotenuse (r) = 29 feet and angle (a) = 79 degrees. This should be enough information to use the trigonometric formula sin a = y / r. All that is left is to substitute the given values into the formula. This result is sin 79 = y / 28. Solving for y, we get y = sin 79 * 28 = 27.4856 feet.

Answer 2

sin 79 degrees = opposite/hypotenuse

= height/ladder length

to solve for height we multiply ladder length to both sides:

28ft * sin79 degree = height of ladder

height of ladder = 27.5ft