Answer:
x(x + 4) = 21
Step-by-step explanation:
Area = length * width.
21 = x + 4 * x
x(x + 4) = 21
I gotchu fam, a rotation is occurring and we know this because it’s rotating 180°. Figures PQRS and P’Q’R’S’ are congruent because they are the same shape and size, just in different places.

Simplify
to 

Both are over 11, so, just sum.


Answer:I'm pretty sure it would be C but that might be wrong
Step-by-step explanation:
Areashaded=areabigcircle-areasmallcircle
areacircle=pir^2
d/2=r
big diameter=20.4, so radius i 20.4/2=10.2cm
small is 10.8/2=5.4
so
big-small
pi10.2^2-pi5.4^2
pi(104.04-29.16)
pi(74.88)
using 3.14=pi
235.1232 cm^2
answer is B