Question

Calculate ZQRP
12 cm
Р
R
18 cm

Answer 1

<QRP = 48.2°

Explanation:

Given:

PR = 18 cm

QR = 12 cm

Required:

<QRP = angle R

Solution:

Reference angle = <R (<QRP)

Adjacent side length = 12 cm

Hypotenuse = 18 cm

Thus:

Cos (R) = 12/18

cos (R) = 0.6667

`R = Cos^(-1)(0.6667)`

`R = 48.1871227`

<QRP = 48.2° (nearest tenth)