How do you find the area of a circle with just the radius?

Oh that's easy! You find out what the radius is.. then the diameter is another one of that number. Example say that the radius is 10 then the diameter is 20 or if the radius is 7 the diameter is 14

Step-by-step explanation:

Step-by-step explanation:

π = pi, and r is the radius.   It's the only value you need to find the area of a circle.  π is usually represented as 3.14, or you can use the π button on your calculator

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!

the answer is a.

135 and 80

step-by-step explanation: