Simplifying Expressions

Objective

simplify and evaluate algebraic expressions

Evaluating Expressions

Remember to use correct order of operations.

Evaluate the expression 2x – 3xy +4y when

x = 3 and y = -5.

To find the numerical value of the expression, simply replace the variables in the expression with the appropriate number.

Example

Evaluate 2x–3xy +4y when x = 3 and y = -5.

Substitute in the numbers.

2(3) – 3(3)(-5) + 4(-5)

Use correct order of operations.

6 + 45 – 20

51 – 20

31

Evaluating Example

1and2when34Evaluate 22 yxyxyx

Evaluating Example

Substitute in the numbers.

1and2when34Evaluate 22 yxyxyx

Evaluating Example

Substitute in the numbers.

1and2when34Evaluate 22 yxyxyx

22 131242

Evaluating Example

Remember correct order of operations.

1and2when34Evaluate 22 yxyxyx

22 131242

Substitute in the numbers.

131244

384

15

Common Mistakes

Incorrect Correct

More Examples