# 6: Expressions and Equations

- Page ID
- 57176

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- 6.1: Evaluating Algebraic Expressions
- In this section we will evaluate algebraic expressions for given values of the variables contained in the expressions.

- 6.2: Combining Like Terms
- A term is a single number or variable, or it can be the product of a number (called its coefficient) and one or more variables (called its variable part). The terms in an algebraic expression are separated by addition symbols.

- 6.3: Adding and Subtracting Polynomials
- Recall that we combine like terms, or terms with the same variable part, as a means to simplify expressions. To do this, add the coefficients of the terms to obtain a single term with the same variable part, but the variable part does not change. This, in addition to the commutative and associative properties of addition, allows us to add polynomials.

- 6.6: Prelude to Solving Linear Equations
- Law enforcement and the military are using drones rather than send personnel into dangerous situations. Building and piloting a drone requires the ability to program a set of actions, including taking off, turning, and landing. This, in turn, requires the use of linear equations.

- 6.7: Use a General Strategy to Solve Linear Equations
- Solving an equation is like discovering the answer to a puzzle. The purpose in solving an equation is to find the value or values of the variable that makes it a true statement. Any value of the variable that makes the equation true is called a solution to the equation. It is the answer to the puzzle!

- 6.8: Use a Problem Solving Strategy
- Now that we can solve equations, we are ready to apply our new skills to word problems. We will develop a strategy we can use to solve any word problem successfully.