science
2.1- Look for a Pattern- 1) Use the given information to find a pattern 2) Use there pattern to solve the problem 3) Check that the answer is reasonable 2.2 -Variable- A letter used to represent a number value in an expression or an equation. Constant- A value that does not change Algebraic Expressions-an algebraic expression which includes numbers and variables 2.3- Like Terms-like terms is terms such as x and 4x with the same variable raised to the same exponent Unlike Terms- unlike terms is terms, such as 2y, and 3x, with different variables or with the same variables raised to the exponent 2.4-Equations- A mathematical statement that says that two expressions have the same value; any number sentence with an =.