To determine the area if the circle, you must know the diameter or the radius of a circle.
If you know the radius of a circle, use this as your formula. Remember: Pi (the greek symbol thingy) is equal to 3.1415. (A is equal to area of the circle and r represents the radius)

If you know the diameter, just divide the diameter to get the radius then use the same equation.
1 quarter note=2 eighth notes
1 eight note=2 sixteenth notes
so
1 quarter note=4 sixteenth note
so
times 3 both sides
3 quarter notes=12 sixteenth notes
Expand the square: 4(x-11)^ =25
4(x-11)(x-11)=25
Distribute : 4(x-11)(x-11)=25
4(x(x-11)-11(x-11))=25
Distribute: 4(x(x-11)-11(x-11))=25
4(x^-11x-11(x-11))=25
Solution: x=17/2
x=27/2
hope that helps
Im not sure what the question is asking but my guess would be c)18.