35.20 is the decimal version
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°
It had to start off negative. Odd powers of negative numbers remain negative, even powers will always be positive no matter what. Every time you add one to the power, you multiply by another negative, changing the sign.
