Question

Can someone tell me what I did wrong? Please
In the diagram BE and AD pass through the center of circle 0 and the area sector AOC is 47.45 square units. What is the area of sector BOC? Use the value pi=3.14 and round your answer to two decimal places.
I had done it this way but was wrong.
HELP PLEASE!!!!
40/360*3.14(0.8)^2
0.2233
22.33

Answer 1

@eliassaab HELP PLEASE I'm doing something wrong

Answer 2

It looks like you found the area of sector AOB

Answer 3

although you should use radius= 8 (not 0.8)

Answer 4

I would still get the wrong answer is my formula wrong???

Answer 5

the next step is to notice that the areas of sector AOB + sector BOC together add up to the area of sector AOC

they tell you the area of AOC= 47.45

using your answer for the area of AOB= 22.33 we can say

area BOC + 22.33= 47.45

Answer 6

you correctly found the area of sector AOB

but I would write it as
40/360*3.14* 8^2 = 22.33

Answer 7

then I would get 25.12
is there an easier way to do this?

Answer 8

There is no easier way. It is a two step process. It is good to go through the thinking, to make sure it makes sense.

Answer 9

Thank you so I need to remember the two steps here!

Answer 10

Let x be the angle AOC
\[
\frac{1}{360} 3.14 8^2 x=47.45\\
x=85= \text {angle } AOC\\
\text{ angle } BOC= 85- 40=45\\
\text { then the area of BOC is} \\
\frac{1}{360} (3.14) 8^2 (45)=25.12
\]

Answer 11

40/360*3.14*8^2 =22.33
BOC+22.33=47.45
BOC=25.12

Answer 12

Thank you @eliassaab

Answer 13

YW