The video tutorial explains how to evaluate an expression by first combining like terms and then substituting given values for the variables. The process begins with identifying and combining like terms, such as 9x and 6x, and 3y and 5y, to simplify the expression to 15x + 8y. Next, the video demonstrates substituting the values 8 for x and 10 for y into the simplified expression. The final step involves evaluating the expression to reach the solution of -40.

What is the first step in solving the problem of evaluating expressions?

• Divide the expression

• Multiply coefficients

• Combine like terms

• Substitute values into the expression

Why is it beneficial to combine like terms before substituting values?

• It increases the coefficients

• It changes the variables

• It simplifies the expression

• It makes the expression longer

Which of the following are like terms?

• 9x and 6y

• 9x and 6x

• 3y and 5x

• 3x and 5y

What is the result of combining 9x and 6x?

• 3x

• 9x

• 15y

• 15x

After combining 3y and 5y, what is the new term?

• 5y

• 3y

• 8y

• 8x

What is the simplified expression after combining like terms?

• 9x + 5y

• 15x + 3y

• 9x + 6x + 3y + 5y

• 15x + 8y

What is the coefficient of x in the simplified expression?

• 6

• 10

• 15

• 8

What is the coefficient of y in the simplified expression?

• 8

• 15

• 10

• 6

What value is substituted for the variable x?

• 6

• 8

• 10

• 15

What value is substituted for the variable y?

• 10

• 6

• 15

• 8