Hello!
To find the area of a circle you do

the "r" stands for radius which is half the diameter
So we do

Which gives us the answer of 314.16
Hope this helps!
Answer:

Step-by-step explanation:
Given

Required
Simplify

Open brackets

Collect Like Terms

Simplify like terms

Step-by-step explanation:
By Pythagoras' Theorem, 6^2 + 8^2 = x^2.
x^2 = 36 + 64 = 100, x = 10.
Answer:

Step-by-step explanation:
We remove the bracket and rearrange the numbers to add them. Only similar variables can be added together.

No because they are not following the same rule