Evaluating Expressions

Front

What is an expression in mathematics?

Back

An expression is a combination of numbers, variables, and operators (such as +, -, *, /) that represents a value.

Front

What does it mean to evaluate an expression?

Back

To evaluate an expression means to calculate its value by substituting the variables with given numbers.

Front

What is the order of operations in mathematics?

Back

The order of operations is a set of rules that dictates the sequence in which calculations are performed: Parentheses, Exponents, Multiplication and Division (from left to right), Addition and Subtraction (from left to right) - often abbreviated as PEMDAS.

Front

Evaluate the expression: -7w² + 2w if w = -4.

Back

-120

Front

Evaluate the expression: ½(10p - 7q) if p = 9 and q = 2.

Back

38

Front

Evaluate the expression: (18 - ab) + 4b if a = -2 and b = -5.

Back

-12

Front

Evaluate the expression: x² - xy if x = 8 and y = -3.

Back

88

Front

Evaluate the expression: (12xy)/(x - y) if x = 3 and y = -1.

Back

-9

Front

What is a variable in an expression?

Back

A variable is a symbol (usually a letter) that represents an unknown value in an expression or equation.

Front

What is a coefficient in an expression?

Back

A coefficient is a numerical factor that multiplies a variable in an expression.