Some of the questions that we did was:

So Mr.Harbeck gave us a circle that has a radius of 16.5 cm.

The next step for us to do was to find the diameter.

The formula to find the diameter is:

If the image is hard to see or it doesn't work it is:

d=2r

d=2x16.5

d= 33 cm

So the next thing we had to find out the circumfrence:

If you don't know what circumfrence is, it is this:

The formula to find the circumfrance for this question is:

C=πd

C=3.14x33=

C=103.6

The next thing we had to do is find the area of this circle:

The formula to find area is

A=πxrxr

A=3.14x16.5x16.5

A= 854.87

Once I demonstrated that to you, I will not post any more pictures.

Another circle we did is one which has a diameter of 15.

For us to find the Radius of a diameter the formula is

R= D/2

R= 15/2

R=7.5

After we find the Radius we should find the circumfrance(we already have the diameter)

C=πd

C=3.14x15

C=47.1

After the circumfrence the last thing we have to do is to find the area.

A=πxrxr

A=3.14x7.5x7.5

A=176.35

Another thing we did in class today was we used a cylinder such as this.

After we break it down it should be like this

Since we have the radius we should go onto the diameter

D=2r

D=2x5

D=10 cm

After the diameter, we should go onto the circumfrence:

C= πD

C=3.14x10

C=31.4

LxW=rectangle

31.4x10

=314 cm2

After circumfrence we should go to Area.

A=πxrxr

A=3.14x5x5=

A= 78.5

TSA=

471 Cm2

Another formula we did to make everything shorter that I put up there was

(2πxrxr)+2xrcrπxh)=

(2x3.14x5x5)+2x5x3.14x10)=

So one of the questions that I'm going to be doing is:

Since it gives us the diameter, I started off with the radius.

R=D/2

R=7/2

R=3.5

Then I went to the Circumfrence:

C=πD

C=3.14x7

C=21.98

LxW= 7x2198

= 153.86

After that, I went to the area:

A=πxrxr

A=3.14x3.5x3.5

A=213.445

Another question is:

There is already the radius so you don't bother with that

D=R2

D=3x2

D=6

C=πD

C=3.14x6

C=18.84

LxW

5x18.84=94.2

Next we do the Area

A=πxrxr

A=3.14x3x3

A=38.26

28.26

+ 18.84

----------------

47.1

+ 94.2

------------

141.3

Another Question is:

D= Rx2

D=3x2

D=6

C=πD

C=3.14x6

C=18.84

LxW

5x18.84=

94.2

A=πxrxr

A-3.14x3x3

A=28.26

28.26

+ 18.84

--------------

47.1

+94.2

-------------------

141.3 cm2

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