# Chapter 10

## Chapter 10.1 (Parallelograms)

To find the area of a parallelogram you multiply base times height.

A=bh

The height will usually be shown by the length that is perpendicular to the base.

The answer should be given in square units.

A=1/2(b#1=b#2)h

A=1/2(4+8)3

A=1/2*12*3

A=6*3

A=18 m squared

## 10.2 (Area of a circle)

The radius of a circle is halfway into the circle.

A=pi*r^2

If they only give you the diameter divide it in half.

The answer should be given in square units.

## 10.2 (Finding the radius)

A=pi*r^2

530.66=3.14*r^2

169=r^2 (divided 530.66 by 3.14)

square root 169 and r

13=r

Using the Area of a Circle to find its Radius

## 10.3 (How to classify solids)

If a solid has two congruent circle bases is called a cylinder.

If it has polygon bases it is called polyhedron.

## 10.3 (What are faces, edges, and vertices.)

Faces: All of the flat surfaces that form the polyhedron.

Edges: Segments where faces meet.

Vertices: Where bases meet at a point.

## 10.4 (Using the net drawing)

Find the area of each face,

then add them up.

2*225+4*450+2250in squared

## 10.5 (Surface area of a pyramid)

S=b+1/2*p*l

S=27.7+1/2*24*6

S=99.7squared units

## 10.5 (Surface area of a cone)

S=pi*r^2+pi*r*l

l= the slant height

Think of slant height as a ball rolling down a pyramid

## 10.6 (Volume of a prism)

V=B*h

For rectangular prisms:

V=l*w*h

For triangular prisms:

V=1/2*both the legs *h

## Two reasons why to find volume.

1: Knowing the volume of a prism would be helpful in real life for someone at a packing company needing to know how much packing foam to put in a package.

2:Or even filling up a classroom with packing peanuts as a joke.

V=pi*r^2*h

(cubed)

## 10.7 (Volume of a pyramid)

V=1/3*B*h

Area of the base= b*h

V=1/3*pi*r^2*h

V=4/3*pi*r^3

## Why find it?

Lets say you want to fill up a ball with air. Finding the area will help you to determine how much to pump into it.