Use the correct order of operations to evaluate algebraic expressions (AF 1.2) Use algebraic terminology correctly (AF 1.4)

a mathematical phrase that contains operations, numbers, and/variables. a letter that represents a value that can change or vary. contains only numbers substitute a given number for the variable contains one or more variables.

x – 5 for x = – 5 7

PEMDAS: 1. Parentheses 2. Exponents 3. Multiply and Divide from left to right. 4. Add and Subtract from left to right.

Substitute 4 for y. Multiply. 2y + 1 for y = 4 2(4) Add. 9

Evaluating Algebraic Expressions with One Variable 6(n + 2) – 4 for n = 5, 6, 7 6(5 + 2) – 4 6(7) – 442 – (6 + 2) – 4 6(8) – 4 48 – (7 + 2) – 46(9) – 4 54 – 450 nSubstituteParenthesesMultiplySubtract 5 6 7

What is the Order of operations?

A. 4x + 3y for x = 2 and y = 1 4(2) + 3(1) B. 9r – 2p for r = 3 and p = 5 9(3) – 2(5) 27 – 10 17

Substitute 3 for x and 4 for y. Multiply. A. 3x + 2y for x = 3 and y = 4 3(3) + 2(4) Add. 17 Substitute 2 for q and 2 for r. Multiply. B. 8q – 3r for q = 2 and r = 2 8(2) – 3(2) 16 – 6 Subtract. 10

Use the expression 1.8c + 32 to convert the temperature from degrees Celsius to degrees Fahrenheit. Boiling point of water at sea level: 100°C Substitute 100 for c. Multiply. 1.8(100) c + 32 Add °C = 212°F Water boils at 212°F at sea level.

Classwork Evaluate each expression for the given value(s) of the variables. 1. 6x + 9 for x = 3 2. x + 14 for x = x + 3y for x = 2, y = 3 4. y(27 – x) for x = 19, y = 6 5. If n is the amount of money in a savings account, then the expression n n can be used to find the amount in the account after it has earned interest for one year. Find the total in the account after one year if $500 is the initial amount $515