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## Praxis Core Math

### Unit 1: Lesson 4

Algebra- Algebraic properties | Lesson
- Algebraic properties | Worked example
- Solution procedures | Lesson
- Solution procedures | Worked example
- Equivalent expressions | Lesson
- Equivalent expressions | Worked example
- Creating expressions and equations | Lesson
- Creating expressions and equations | Worked example
- Algebraic word problems | Lesson
- Algebraic word problems | Worked example
- Linear equations | Lesson
- Linear equations | Worked example
- Quadratic equations | Lesson
- Quadratic equations | Worked example

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# Creating expressions and equations | Lesson

## What are expressions and equations?

On the test, we will be asked to create

and based on verbal descriptions. These expressions and equations will involve the , but will not use more advanced operations such as exponents.Some questions will ask for expressions or equations based on their verbal description or a real-world context. To create these expressions and equations, we need to familiarize ourselves with the relationship between key words, real-life scenarios, and mathematical operations.

### What skills are tested?

- Translating sentences to mathematical expressions
- Translating sentences to equations

## How do we translate sentences to expressions and equations?

In addition to the words

, , , , and , we are often presented with other phrases that describe these same mathematical operations. Some of the most common ones are listed in the table below.English | Math |
---|---|

The sum of a and b | a, plus, b |

b is added to... | plus, b |

The difference between a and b, b is subtracted from a | a, minus, b |

The product of a and b | a, times, b |

b times, b of... | b, times |

The quotient of a and b | a, divided by, b or start fraction, a, divided by, b, end fraction |

(The result) is | equals |

A certain number, an unknown quantity | x, y, etc. |

To translate verbal descriptions of mathematical operations:

- Identify any key words or phrases that indicate an operation.
- Combine the individual operations into an expression or equation. Make sure to preserve the order of operations.

## How do we translate real-world contexts to expressions and equations?

In questions with real-world contexts, the mathematical operations are often described by action verbs and comparative phrases. Some more ways we convey mathematical information are listed in the table below.

English | Math |
---|---|

b more than a | a, plus, b |

Increased by b | plus, b |

b less than a | a, minus, b |

Decreased by b, reduced by b | minus, b |

b times (as many) | b, times |

Double, twice | 2, times |

Triple | 3, times |

To translate verbal descriptions of mathematical operations:

- Identify any key words or phrases that indicate an operation.
- Combine the individual operations into an expression or equation. Make sure to preserve the order of operations.

## Practice

## Things to remember

To translate verbal descriptions of mathematical operations:

- Identify any key words or phrases that indicate an operation.
- Combine the individual operations into an expression or equation. Make sure to preserve the order of operations.

English | Math |
---|---|

The sum of a and b | a, plus, b |

b more than a | a, plus, b |

Increased by b, b is added to... | plus, b |

The difference between a and b, b is subtracted from a, b less than a | a, minus, b |

Decreased by b, reduced by b | minus, b |

The product of a and b | a, times, b |

b times (as many), b of... | b, times |

Double, twice | 2, times |

Triple | 3, times |

The quotient of a and b | a, divided by, b or start fraction, a, divided by, b, end fraction |

(The result) is | equals |

A certain number, an unknown quantity | x, y, etc. |

## Want to join the conversation?

- What Grade is This For?(8 votes)
- I think this is grade 9 algebra, Thats what im learning now.(1 vote)

- the math is not mathing(4 votes)
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