Write Expressions and Equations

An expression is a number, a variable, or a combination of numbers and variables and operation symbols. An equation is made up of two expressions connected by an equal sign.

Terms whose variables (such as x or y) with any exponents (such as the 2 in x²) are the same.

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​Examples:

7x and 2x are like terms because they are both "x".

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3x² and −2x² are like terms because they are both "x²".

These are like terms that can get added or subtracted together.

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​​Examples:

7x and 2x are like terms because they are both "x". When combined, they become 9x

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3x² and −2x² are like terms because they are both "x²". When combined, they become x²

Now, how do we solve?

Solving ​2-step & multistep equations

How are these connected to word problems?

• 5 more than a number

• a number increased by 5

• ​5 times as big

• ​half the size

• 11 less than a number

• twice the amount

• the product of 3 and a number

• The quotient of a number and 7

• one tenth of a number

​There are twice as many women as men in a class on auto repair. If there are 24 students in the class, how many are women?

The ticket prices for a play are $12 for adults and $8 for children. One evening, the box office sold 200 tickets. If the total box office receipts were $2240, how many adult tickets were sold?

Consecutive Numbers: numbers that follow in counting order

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1,2,3 <-- consecutive numbers

2,4,6 <-- consecutive even numbers​

​1,3,5 <-- consecutive odd numbers

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The sum of three consecutive numbers is 105. What is the greatest of the three numbers?

The sum of three consecutive numbers is 180. What is the smallest of the three numbers?

Distribution​

• ​This is when a factor is "shared" over an expression in parenthesis

• ​For example:

  • ​a(b + c) = a*b + a*c