Question

find pr.
write your answer as an integer or as a decimal rounded to the nearest tenth.
$pr = \square$
submit

Explanation:

Step1: Identify adjacent side, hypotenuse

In right $\triangle QRP$, $\angle R=63^\circ$, adjacent side to $\angle R$ is $QR=3.5$, hypotenuse is $PR$.

Step2: Use cosine ratio formula

Cosine of an angle is $\frac{\text{adjacent}}{\text{hypotenuse}}$.
$\cos(63^\circ) = \frac{QR}{PR}$

Step3: Rearrange to solve for PR

$PR = \frac{QR}{\cos(63^\circ)}$
Substitute $QR=3.5$, $\cos(63^\circ)\approx0.4540$:
$PR = \frac{3.5}{0.4540} \approx 7.7$

Answer:

7.7