Correct Answer: Option A

Explanation

\(PR^2 = PQ^2 + RQ^2 - 2(PQ)(RQ)cos Q\)

\(\implies cos Q = \frac{PQ^2 + RQ^2 - PR^2}{2(PQ)(RQ)}\)

\(\implies cos Q = \frac{8^2 + 5^2 - 7^2}{2\times8\times5}\)

\(\implies cos Q = \frac{64 + 25 - 49}{80}\)

\(\implies cos Q = \frac{40}{80} = 0.5\)

\(\implies Q = cos^{-1} (0.5) = 60^0\)

\(\therefore x = 60^0\)

There is an explanation video available below.

• how to write a semi formal letter? Answer this

  1 Answers   ·   English Language   ·   4 hours ago
• What is the probability that pupil ohosen at random will pass the rest if the pass mark is :? Answer this

  1 Answers   ·   Mathematics   ·   4 hours ago
• delsu post utme form out for 2024? Answer this

  0 Answers   ·   Law   ·   13 hours ago