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A 24-foot ladder leaning against a wall makes a 30 ° angle with the ground . How high up on the building is the top of the ladder ?

HELP ASAP

User Ross R
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1 Answer

5 votes

Answer:


12\:\mathrm{ft}

Explanation:

When the ladder is leaning against the wall, a 30-60-90 triangle is formed. The ladder acts as a 24-foot hypotenuse. Because the height is facing the
30^(\circ) angle, the height is half the hypotenuse (30-60-90 rules). If you forget the side rules for a 30-60-90 triangle, simply use basic trig on the right triangle:


\sin 30^(\circ)=(h)/(24),\\h=24\sin 30^(\circ),\\h=24\cdot (1)/(2),\\h=\fbox{$12\:\mathrm{ft}$}.

User Hunter Zhao
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