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## Praxis Core Math

### Unit 1: Lesson 5

Geometry- Properties of shapes | Lesson
- Properties of shapes | Worked example
- Angles | Lesson
- Angles | Worked example
- Congruence and similarity | Lesson
- Congruence and similarity | Worked example
- Circles | Lesson
- Circles | Worked example
- Perimeter, area, and volume | Lesson
- Perimeter, area, and volume | Worked example

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# Perimeter, area, and volume | Lesson

## What are perimeter, area, and volume?

The

**perimeter**, start color #aa87ff, P, end color #aa87ff, of a polygon is the total length around the polygon's edges. When we add up all the side lengths of a polygon, we get its perimeter. For the figure below, the perimeter is:The

**area**, start color #e84d39, A, end color #e84d39, of a polygon is the amount of flat space inside the polygon's edges. Area is measured in square units such as square miles. Different polygons have their own area formulas.The

**volume**, start color #a75a05, V, end color #a75a05, of an object is the amount of space that object occupies. Volume is measured in cubic units such as cubic centimeters.### What skills are tested?

- Calculating the perimeter of a polygon
- Calculating a side length given the perimeter
- Calculating the area of a polygon
- Calculating a length given the area
- Calculating the volume of an object
- Calculating a length given the volume

## Which perimeter formulas are on the test?

For a s. The formula is:

, each side has the same length, For a start color #11accd, l, end color #11accd, and two sides have width start color #1fab54, w, end color #1fab54. The formula is:

, two sides have length With each formula, we can also calculate the side lengths when start color #aa87ff, P, end color #aa87ff is given. To do so, we:

- Write down the appropriate equation.
- Plug in known values.
- Solve for s, start color #11accd, l, end color #11accd, or start color #1fab54, w, end color #1fab54.

## Which area formulas are on the test?

For a s. The formula is:

, each side has the same length, For a start color #11accd, l, end color #11accd, and two sides have width start color #1fab54, w, end color #1fab54. The formula is:

, two sides have length For a start color #01a995, b, end color #01a995 and the height start color #ca337c, h, end color #ca337c. The formula is:

, we're concerned with the base For a start color #01a995, b, end color #01a995 and the height start color #ca337c, h, end color #ca337c, the formula is:

with base With each formula, we can also calculate one of the linear dimensions when start color #e84d39, A, end color #e84d39 is given. To do so, we:

- Write down the appropriate equation.
- Plug in known values.
- Solve for the linear dimension.

## Which volume formulas are on the test?

For a start color #11accd, l, end color #11accd, width start color #1fab54, w, end color #1fab54, and height start color #ca337c, h, end color #ca337c, the formula is:

with length We can also calculate one of the linear dimensions when start color #a75a05, V, end color #a75a05 is given. To do so, we:

- Write down the volume equation.
- Plug in known values.
- Solve for start color #11accd, l, end color #11accd, start color #1fab54, w, end color #1fab54, or start color #ca337c, h, end color #ca337c.

## Your turn!

## Things to remember

Shape | Perimeter (P) formula |
---|---|

P, equals, 4, s | |

P, equals, 2, left parenthesis, l, plus, w, right parenthesis |

Shape | Area (A) formula |
---|---|

A, equals, s, squared | |

A, equals, l, w | |

A, equals, b, h | |

A, equals, start fraction, 1, divided by, 2, end fraction, b, h |

Shape | Volume (V) formula |
---|---|

V, equals, l, w, h |

## Want to join the conversation?

- can volume, area, and permeter have a formula together.(3 votes)
- Nope, there is a seperate formula for each.(1 vote)

- That was really ok and hard did not learn fraction perimeter volume and area!(2 votes)
- i tink ima 30938948599892839289219348 gazeion years(1 vote)
- cool im stupid(1 vote)
- What the heck is this from ohio?(1 vote)
- How do you solve for the volume of a cylinder(0 votes)
- Find the area of its circular base, then multiply by the height.(1 vote)