I think your question should read "A circle has an AREA of 81 PI square units...)
Circle Area = PI * radius^2
81 PI = PI * radius ^2
radius^2 = 81 PI / PI
radius^2 = 81
radius = 9
Therefore circle diameter = 9 * 2 = 18
Https://www.google.com/search?q=how+to+find+herons+formula&rlz=1C1CHBF_enUS712US712&oq=how+to+find+h... look at the first thing that comes up on the url page
Answer & Step-by-step explanation:
Devin runs an average of 15 min in 7 days
15 * 7 = 105 minutes
She has a goal of running 10² min. in 7 days
10² = 100 minutes
Will she complete her running goal in 7 days?
Yes. On average, she will run 105 minutes in seven days which is more than her 100 minute goal.
3/4
Step-by-step explanation:
If you cut a whole pie into two you get two (2) ½ pieces
1 ÷ 2 = ½
When you cut the two ½ pieces into two you get four (4) ¼ pieces;
½ ÷ 2 = ¼
When you cut the four ¼ pieces into two you get 8 1/8 pieces;
¼ ÷ 2 = ¹/8
Therefore the whole pie at this point is made up of 8 ¹/8 pieces. When two (2) of these pieces are eaten we are left with 6 ¹/8 pieces;
8 – 2 = 6
The portion of the pie left therefore is;
6 * ¹/8 pieces
= ⁶/8
= ³/4