Expressions and Variables in Algebra

The video tutorial explains how to translate tables into algebraic expressions by using variables to represent unknown numbers. It covers various operations such as addition, subtraction, multiplication, and division applied to different scenarios like length, cost, quantity, time, and distance. The tutorial emphasizes understanding the meaning of terms like 'sum', 'difference', 'twice', and 'triple' in the context of algebraic expressions.

What variable is used to represent an unknown number in the first section?

• n

• x

• z

• y

How do you express twice the sum of a number and three?

• n + 3

• 2(n + 3)

• n + 6

• 2n + 3

What is the expression for double the length?

• l/2

• l + 2

• 2l

• l - 2

How do you express double the length decreased by six?

• 2l + 6

• l - 6

• 2l - 6

• l + 6

What variable is used to represent cost?

• c

• k

• m

• p

How do you express two times the difference of the cost and twenty?

• c + 20

• 2(c - 20)

• c - 40

• 2c - 20

What is the expression for the difference of five and a quantity divided by two?

• q - 5/2

• 5 - q/2

• (5 - q)/2

• 5/(q - 2)

What variable is used to represent time?

• t

• s

• r

• q

How do you express triple the amount of time increased by five?

• 3t + 5

• t + 15

• t + 5

• 3(t + 5)

What is the expression for the sum of negative four and twice the distance?

• -4d + 2

• 2d - 4

• d - 4

• -4 + 2d