21.3 is the correct answer.
Answer:
64
Step-by-step explanation:
cause I did it in classs
I think you mean circumference...Area is

. We have the area so we need to use it to solve for the radius which we will then use in the circumference formula.

. Divide both sides by pi to get

. Of course the simplification of the left side gives us

and r = 4. Now fill that in to the circumference formula, which is

, to get C

which is a circumference of
Hello,
cos 160°=-q
cos 20°=-cos 160°=q
sin 20°=√(1-q²)=sin 160°
tan -20°=tan 160=√(1-q²)/-q
cos 70°=sin 20°=√(1-q²)
Answer:
The answer is (a²+1)(2a+1)