Evaluating and Writing Algebraic Expressions

In this video, Mr. Void teaches students how to evaluate algebraic expressions by substituting numbers for variables and using the order of operations. The lesson includes several examples, demonstrating the process of substitution and calculation. Additionally, the video covers writing algebraic expressions for real-world scenarios, such as calculating costs. Students are encouraged to pause and practice with provided problems, and the video concludes with a set of challenge problems.

What does 'evaluate' mean in the context of algebraic expressions?

• To simplify the expression

• To rewrite the expression in a different form

• To substitute a number for a variable and find the value

• To solve for the variable

What is the correct order of operations?

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

• Parentheses, Exponents, Multiplication/Division (left to right), Addition/Subtraction (left to right)

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

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

If a = 3, b = 5, and c = -1, what is the value of the expression 6a - 3b + 8?

• 11

• 9

• 10

• 12

What is the result of the expression a^2 * b + 2 if a = 3 and b = 5?

• 27

• 35

• 63

• 45

What should you do first when evaluating the expression 3a - 2b + 3 if a = 3 and b = 5?

• Add 3 to 2b

• Subtract 2b from 3a

• Multiply 3 by a and 2 by b

• Add 3 to 3a

How do you write an expression for the total cost of gasoline if gasoline is $3 per gallon and g represents the number of gallons?

• 3 - g

• g/3

• 3g

• 3 + g

What is the expression for the total charge if a company charges $40 plus $11.50 per hour and h represents the number of hours?

• 40h - 11.50

• 40h + 11.50

• 40 + 11.50

• 40 + 11.50h

How would you write an expression for the amount of feed left if you start with 15 pounds and use 2 pounds per day, with d representing the number of days?

• 2d - 15

• 15 - 2d

• 15 + 2d

• 15d - 2

If 65% of 300 packages are left, what is the expression to represent this?

• 0.65 + 300

• 300 / 0.65

• 300 - 0.65

• 0.65 * 300

What is the value of the expression 3 * 5 / 5?

• 1

• 3

• 5

• 15