Answer:
Hi,
Step-by-step explanation:
PR²=PQ²+QR²-2*PQ*QR*cos(51°)
=15²+12²-2*15*12*cos(51°)
=142,444659....
PR=11.9350...
PQ²=QR²+PR²-2*QR*PR*cos(R)
cos(R)=(12²+142.444...-15²)/(2*12*11.9350...)=0,21451112....
angle R=77,61315...°≈77.6°
angle P=180°-51°-77.6°≈51,4°
