Question

help area of shaded region

Answer 1

@

Answer 2

Can you find area of semicircle?

Answer 3

Semicircle is just half the circle.

So it's like finding area of circle, but THEN you divide it by 2.

Answer 4

yes that 4.71cm2

Answer 5

@geerky42

Answer 6

was that right @geerky42 ?

Answer 7

@Michele_Laino

Answer 8

No.

Answer 9

Area of circle is \(A = \pi r^2\)
So to find area of semicircle, you just use this formula then divide by 2.

Answer 10

but you said semi circle so wouldn't it be A=1/2pi r

Answer 11

My point is, to find semicircle, you just find area of circle, then divide by 2. Get it?

Also it's \(\pi r^2\), not just \(\pi r\).

Answer 12

So area of semicircle is \(\dfrac{\pi r^2}{2}\)

Answer 13

@geerky42 so 9.42cm2/2=4.71cm2

Answer 14

Radius is 3, so you have \(\dfrac{\pi(3)^2}{2} = \dfrac{9\pi}{2}\approx 14.137\)

Answer 15

Just remember that \(\pi\approx3.14\)

Answer 16

yes you told me that, thats how remember what pi is but how did you get the 9pi over 2

Answer 17

\(3^2 = 9\)

Answer 18

you divide 2 because semicircle

Answer 19

Is that clear?

Answer 20

yes kinda

Answer 21

thank you though @geerky42

Answer 22

Well, we are not done

Answer 23

we got area of semicircle. Now we need to subtract that by area of triangle

Answer 24

(Area of semicircle) - (Area of triangle)

Right?

Answer 25

yea

Answer 26

Ok. Area of triangle is \(\dfrac{1}{2}bh\)

Do you know base and height here?

Answer 27

but we don't have the area of the triangle so we need to solve for the triangle

Answer 28

Right.

Answer 29

so 3 would be our height

Answer 30

so how would you find the base given only the height

Answer 31

We don't really have to use height to find base.

Triangle and semicircle share same base, right?

Answer 32

yes

Answer 33

do the MAGIC! drawing thing geerky

Answer 34

We know that radius of semicircle is 3, so what is diameter?

Answer 35

:D

Answer 36

hahaaaa @camacho01erick that was the best response

Answer 37

lol. though I don't see the need to drawing something here lol.

Answer 38

1.5

Answer 39

maybe I will do magic thing once asker solve something like gif of victory lol.

Answer 40

@Mromanos96 No

\(d = 2r\), right?

Answer 41

k

Answer 42

yes

Answer 43

6