Answer:
x = 73
Step-by-step explanation:
A circle is 360 degrees
4x-5 + x = 360 degrees
5x - 5 = 360 degrees
5x = 365 degrees
Divide by 5
5x/5 = 365/5
x =73
If b was 3 a will be 6 because 2*3=6
and for the second part b will be 3.5 because 2*3.5=7
Area ( If you know the circumference) :
C^2 / (4×3.14) Brackets are important!
So you have to type :
53.38^2/(4×3.14)
= 226.865
X=45 since 90-45=45
Hope this helps