Evaluating Expressions with Variables

The video tutorial demonstrates how to evaluate algebraic expressions by substituting a given value for the variable x. Three examples are provided: evaluating -3x-6 when x=7, -10x-9 when x=8, and 8x+10 when x=10. Each example involves substituting the value of x into the expression, performing arithmetic operations, and arriving at the final result.

What is the result of the expression -3x - 6 when x equals 7?

• -27

• -30

• -24

• -21

If x is 7, what is the value of -3 times x?

• -18

• -21

• -24

• -27

What is the final result of -10x - 9 when x is 8?

• -90

• -79

• -80

• -89

Calculate -10 times 8.

• -100

• -90

• -70

• -80

What is the result of subtracting 9 from -80?

• -89

• -79

• -90

• -81

What is the result of 8x + 10 when x equals 10?

• 90

• 80

• 100

• 70

If x is 10, what is the value of 8 times x?

• 80

• 70

• 100

• 90

What is the sum of 80 and 10?

• 70

• 80

• 100

• 90