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Ch. 1 - Angles and the Trigonometric Functions
Blitzer - Trigonometry 3rd Edition
Blitzer3rd EditionTrigonometryISBN: 9780137316601Non è quello che usi tu?Cambia libro di testo
Capitolo 1, Problema 53

In Exercises 49–54, find the measure of the side of the right triangle whose length is designated by a lowercase letter. Round answers to the nearest whole number.
Right triangle QRP with angle 39° and side QR measuring 51 m.

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1
Identify the sides of the right triangle relative to the given angle of 39°. Here, side QR (51 m) is opposite angle P, and side RP is adjacent to angle P.
Determine which side length you need to find. For example, if you want to find side QP (the hypotenuse), use the sine or cosine function based on the given angle and known side.
Set up the trigonometric ratio using the angle and known side. For example, if finding the hypotenuse QP, use the cosine function: \(\cos(39^\circ) = \frac{\text{adjacent}}{\text{hypotenuse}} = \frac{51}{QP}\).
Rearrange the equation to solve for the unknown side. For the hypotenuse, multiply both sides by QP and then divide both sides by \(\cos(39^\circ)\) to isolate QP: \(QP = \frac{51}{\cos(39^\circ)}\).
Calculate the value using a calculator (make sure it is in degree mode), then round the answer to the nearest whole number as required.

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