Algebraic Expressions

Explain how a variable is different from a constant.

• Variables are always positive, while constants can be negative.

• Variables are always even, while constants can be odd.

• Variables can change in value, while constants remain the same.

• Variables are always whole numbers, while constants can be fractions.

Complete a table of values for the expression 3a.

• 4, 6, 8, 10

• 6, 9, 12, 15

• 5, 7, 9, 11

• 10, 13, 16, 19

Write an algebraic expression for 'A number times six'.

• 6a

• a + 6

• a ÷ 6

• 6 - a

Evaluate the algebraic expression 6b when b = 20.

• 132

• 126

• 120

• 138

Which expression shows the total number of scoops needed to feed the entire litter of puppies, where 'p' represents the number of puppies and each require 2 small scoops of food?

• 2÷p

• p+2

• 2p

• p + p

Write an algebraic expression for 'A number divided by two'.

• a ÷ 2

• 2 - a

• a + 2

• 2a

Evaluate the algebraic expression 13x when x = 13.

• 156

• 169

• 143

• 130

Write an algebraic expression for 'Three-quarters of a number'.

• 4a/3

• 3a/4

• 4/3a

• 3/4a

Evaluate the algebraic expression a ÷ 5 when a = 35.

• 6

• 5

• 8

• 7

Evaluate the algebraic expression 7y when y = 14.

• 98

• 91

• 84

• 77