Presentation Transcript
1-1Algebraic Expressions & Order Of Operations :1-1Algebraic Expressions & Order Of Operations Variable—A symbol, usually a letter, that represents one or more numbers.
Algebraic Expression—A mathematical sentence consisting of:
1. Numbers
2. Variables
3. Operation Symbols
**NOTE**
THERE ARE NO EQUAL SIGNS!
An equal to symbol would make the expression an EQUATION!
Slide 2:Order Of Operations—The sequence in which expressions are simplified or evaluated.
1. Parentheses
2. Exponents
3. Multiplication and Division
FROM LEFT TO RIGHT!
4. Addition and Subtraction
FROM LEFT TO RIGHT! 1-1Algebraic Expressions & Order Of Operations
Slide 3:Ex. 1. Write an algebraic expression for each word phrase.
a. Five more than a number
5 + x
x + 5
b. The number of minutes in p hours
60p 1-1Algebraic Expressions & Order Of Operations ALWAYS write addition expressions with VARIABLE FIRST!!! ALWAYS write multiplication expressions with VARIABLE SECOND!!! NO MULTIPLICATION SIGNS IN EXPRESSIONS USING VARIABLES!!
Slide 4:c. The number of sandwiches (s) per person if there are 6 people
s/6
d. $8 less than what your friend (f) makes
f – 8 1-1Algebraic Expressions & Order Of Operations 6/s would be incorrect! “less than” ALWAYS means to SWITCH!! Ex. 1. Write an algebraic expression for each word phrase.
Slide 5:1-1Algebraic Expressions & Order Of Operations Ex. 2. Evaluate each expression for n=6.
a. 5n + 4
5(6) + 4
30 + 4
34 b. (3n – 2) ÷ 4 + 8n – 11
(3(6) – 2) ÷ 4 + 8(6) – 11
(18 – 2) ÷ 4 + 8(6) – 11
16 ÷ 4 + 8(6) – 11
4 + 8(6) – 11
4 + 48 – 11
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