Exploring Variables and Algebraic Expressions

What is a variable in algebra?

• A number that is always constant

• A letter that stands for a number that can change

• A fixed value in an equation

• A combination of numbers and operations

Which of the following is an expression?

• 3n + 7

• n = 5

• 3 + 7

• 7

In the expression 3n + 7, if n = -2, what should be done first?

• Subtract 7 from -2

• Multiply -2 by 3

• Divide -2 by 3

• Add 7 to -2

What is the value of the expression 3n + 7 when n = -2?

• -5

• 5

• -1

• 1

What does PEMDAS stand for in order of operations?

• Parentheses, Exponents, Multiplication, Division, Addition, Subtraction

• Parentheses, Exponents, Multiplication, Division, Subtraction, Addition

• Parentheses, Exponents, Multiplication, Addition, Subtraction, Division

• Parentheses, Exponents, Division, Multiplication, Addition, Subtraction

Evaluate the expression 10 + 5x for x = 2.

• 20

• 15

• 25

• 30

What is the result of 2n^2 - 7 when n = -3?

• 18

• 11

• 20

• 5

Identify the terms in the expression 4x^2 + 7.

• 4, x^2, 7

• 4x^2, 7

• 4, x, 2, 7

• 4x, 2, 7

What is a binomial?

• An expression with four terms

• An expression with two terms

• An expression with one term

• An expression with three terms

How many terms are in the expression 3x + 2y - 7?

• 1

• 2

• 4

• 3