Multiple choice

In $\Delta$PQR, right-angled at Q, PR + QR = 25 cm and PQ = 5 cm. Find the respective values of sin P, cos P and tan P.

  1. 12/13, 5/13 and 12/5

  2. 12/13, 12/5 and 5/13

  3. 5/13, 12/13 and 12/5

  4. 12/5, 12/13 and 5/13
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 $\Delta$PQR is right-angled at Q.

Let                   QR =   x cm                         PR  =  (25 - x) cm                      PR2  =    PQ2  + QR2                                    (25 - x)2 =    (5)2 + x2 $\Rightarrow$       625 + x2 - 50x   = 25 + x2                                             $\Rightarrow$                       50x    =   600 $\Rightarrow$                           x       =  12 Thus, in  $\Delta$PQR, PQ = 5 cm, QR  = 12 cm and PR  = 13 cm. Therefore, sin P = QR/ PR  = 12 / 13, cos P = PQ / PR = 5 / 13 and tan P = QR/ PQ = 12/ 5.

Keep practicing — related questions