Key Concepts

• The addition and multiplication properties of equality allow the same operation to be performed on both sides of an equation
• To solve an equation containing an absolute value, first isolate the absolute value then write two equations: $|u| = c$ and $|u| = -c$
• Use the distributive property to eliminate parentheses in equations before collecting and combining like terms.
• Use the multiplication property of equality to eliminate fractions from equations by multiplying both sides by the LCD.
• Eliminate decimals from an equation by multiplying both sides by a sufficient factor of 10.
• Equations may have one unique solution, no solutions, or an infinite number of solutions.

Glossary

coefficient a number multiplying a variable

equation a mathematical statement of equivalency between two expressions

expression groups of terms connected by addition or subtraction

term a single number, or variables and numbers connected by multiplication

variable a symbol that stands for an unknown quantity, often represented by letters such as $x, y,$ or $z$.