# Chapter 10

### Hour 2 (Sydney W)

## Vocabulary

Area: the number of square units covered by a figure

Base: the lowest part or edge that a shape rests on

Height: the perpendicular distance between the side whose length is the base and the opposite side or vertex

Circle: the set of all points in a plane that are the same distance, called the radius, from a fixed point, called the center

Radius: the distance between the center and any point on the circle

Pi: the ratio of the circumference of a circle to its diameter

Trapezoid: a quadrilateral with exactly one pair of parallel sides

Parallelogram: a quadrilateral with both pairs of opposite sides parallel

Rhombus: a parallelogram with four congruent sides

## All Formulas in 10.1

A = b * h

A = 1/2 * (b1 + b2) * h

## A = b * h

Area of a rectangle, parallelogram, and square.

## A = 1/2 * (b1+b2) * h

Area of a trapezoid.

## Lets Practice:

Answer: 70 cm squared

## Vocabulary

Area: the number of square units covered by a figure

Circle: the set of all points in a plane that are the same distance, called the radius, from a fixed point, called the center

Radius: the distance between the center and any point on the circle

Diameter: the distance across a circle through the center

Circumference: the distance around a circle

Pi: the ratio of the circumference of a circle to its diameter

## All Formulas in 10.2

Area = Pi * radius squared

Circumference = pi * radius * 2

Circumference = pi * diameter

Diameter = radius * 2

Area of Two Circles = 2 * pi * radius squared

## Area = pi * radius squared

Area of a circle. Area of two circles is: 2 * Pi * radius squared

## Lets Practice (use 3.14 for pi)

Answer = 113.04 cm squared

## Area = 2 * pi * radius squared

Area of two circles

## Circumference = 2 * pi * radius

Circumference = pi * diameter

Diameter = 2 * radius

## Vocabulary

Net: a two-dimensional representation of a solid. This pattern forms a solid when it is folded.

Surface Area: the sum of the faces of an object

## S = 2B + Ph

(Surface Area of a Prism)

S = surface area

B = area of the base

P = perimeter of the base

h = height

## Lets Practice

Answer: 96 ft squared

## S = 2B + Ch

S = 2 * pi * radius squared + pi * diameter (radius * 2)

(Surface Area of a Cylinder)

S = surface area

B = area of the base

C = circumference

h = height

## Lets Practice (use 3.14 for pi)

Answer: 246.08 in squared

## Vocabulary

Slant Height: the height of a lateral face, that is any face that is not the base

## S = B + 1/2 * P * l

(Surface Area of a Pyramid)

S = surface area

B = area of base

P = number of triangles

l = area of each triangle

## Lets Practice

Answer: 1,425 ft squared

## S = pi * radius squared + pi * radius * l

(Surface Area of a Cone)

S = surface area

l = slant height

## Lets Practice (use 3.14 for pi)

Answer: 75 cm squared

## Vocabulary

Volume: the measure of the amount of space an object occupies

## V = B * h

(Volume of a Cylinder)

V = volume

B = area of base (pi * radius squared)

h = height

## Lets Practice (use 3.14 for pi)

Answer: 50.24 cm cubed

## V = B * h

Volume of a Prism

## Lets Practice

Answer: 1920 m cubed

## Vocabulary

Pyramid: A solid, formed by polygons, that has one base. The base can be any polygon, and the other faces are triangles.

Cone: A solid with one circular base

Volume: the measure of the amount of space an object occupies

## V = B * h * 1/3

Volume of a Pyramid

## Lets Practice

Answer 112 in cubed

## V = 1/3 * B (pi * radius squared) * h

Volume of a Cone

## Lets Practice (use 3.14 for pi)

Answer: 1,004.8 m cubed

## S = 4 * pi * radius squared

Surface area of a sphere

## V = 4/3 * pi * radius cubed

Volume of a Sphere

## Let's Practice

use 3.14 for pi and round to the nearest tenths if necessary

Answer: 267.9

## Review with real life tie ins

## Wrapping a present

A party store sells wrapping paper with two square feet on each role. You are wrapping a present and you need to find how much wrapping paper you need. The length of the box is 3 feet and the width is 2 feet. The height is 2 feet as well. How many rolls of wrapping paper do you need to cover the present? Answer: 6 rolls

## How It's Made : Tennis Balls

They need to know how big the molds have to be, how much felt is needed, and how big the cylinders need to be to fit the tennis balls just right.