Evaluating Expressions with Variables

The video tutorial explains how to evaluate mathematical expressions with variables. It starts with a simple expression 'a + b' and demonstrates how to substitute values for 'a' and 'b' to find the result. The tutorial then progresses to a more complex expression '10x - 3y', showing how to substitute values for 'x' and 'y' and apply the order of operations to evaluate the expression. The video concludes with an encouragement to practice similar exercises.

What is the result of the expression 'a + b' when a = 5 and b = 7?

• 13

• 10

• 11

• 12

If 'a' is 5 and 'b' is 7, what operation do you perform to find the value of 'a + b'?

• Subtraction

• Multiplication

• Addition

• Division

What is the expression '10x - 3y' when x = -1 and y = 5?

• -25

• 5

• -5

• -15

In the expression '10x - 3y', what is the result of 10 times x when x = -1?

• 1

• -10

• 0

• 10

What is the result of 3 times y in the expression '10x - 3y' when y = 5?

• 25

• 20

• 15

• 10

What operation is performed first in the expression '10x - 3y' according to the order of operations?

• Subtraction

• Division

• Addition

• Multiplication

What is the final result of the expression '10x - 3y' after performing all operations when x = -1 and y = 5?

• -25

• -10

• -5

• -15

In the expression '10x - 3y', what is the result of subtracting 15 from -10?

• -35

• -15

• -25

• -5