PQRS is a rhombus of side 16cm. The diagonal |QS| = 20cm. Calculate, correct to the nearest degree, ∠PQR
A
51o
B
64o
C
77o
D
103o
Verified Correct Answer: D.
Step-by-Step Mathematical Solution
cos\(\alpha\) = \(\frac{10}{16}\) = 0.625
\(\alpha\) = cos-1(0.625)
= 51.3º
∠PQR = 2\(\alpha\)
= 2(51.3º)
= 102.6
= 103º
Source: WAEC / JAMB / NECO Classroom Archive (Record #26509)