- Addition Property of Equality: Adding the same number to each side of an equation produces an equivalent expression.
- Constant of Proportionality: The constant value of the ratio of two proportional quantities x and y; usually written y = kx, where k is the constant of proportionality. In a proportional relationship, y = kx, k is the constant of proportionality, which is the value of the ratio between y and x.
- Direct Proportion (Direct Variation): The relation between two quantities whose ratio remains constant. When one variable increases the other increases proportionally: When one variable doubles the other doubles, when one variable triples the other triples, and so on. When A changes by some factor, then B changes by the same factor: A=kB, where k is the constant of proportionality.
- Division Property of Equality: States that when both sides of an equation are divided by the same number, the remaining expressions are still equal
- Equation: A mathematical sentence that contains an equal sign
- Inequality: A mathematical sentence that contains the symbols >, <, ≥, or ≤.
- Inverse Operation: A mathematical process that combines two or more numbers such that its product or sum equals the identity.
- Multiplication Property of Equality: States that when both sides of an equation are multiplied by the same number, the remaining expressions are still equal.
- Proportion: An equation which states that two ratios are equal.
- Subtraction Property of Equality: States that when both sides of an equation have the same number subtracted from them, the remaining expressions are still equal.
- Term: A number, a variable, or a product of numbers and variables.
- Variable: A letter or symbol used to represent a number or quantities that vary.
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