Warm Up: Use Chunking and Order of Operations to solve.
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Transcript of Warm Up: Use Chunking and Order of Operations to solve.
Warm Up: Use Chunking and Order of Operations to solve.
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( )4 3 6 2 10
24 2 18 5 1 [ ( )]
50 36 4 5
8 5 4
10 6
Learning Target Read Learning Target #2. Evaluating Algebraic Expression Problems
are like this: Evaluate if x = 2 and y = 4
Rate your self in the “B” (before) section for LT #2 on how well you can do problems like these.
23 yx
Evaluating Algebraic
Expressions
ExpressionsAn expression is NOT an equation because it DOES NOT have an equalsign. There are 2 types of expressions.
5 + 84 Numerical3x + 10 Algebraic
Notice there are no equal signs in these Expression (so they are not equations!)
Numerical ExpressionA numerical expression containsonly numbers and symbols.
(5 3) + 8
Algebraic ExpressionAn algebraic expression contains only numbers, symbols, and variables. It is sometimes referred to as a variable expression.
The product of 3 and x 3xThe sum of m and 8 m + 8The difference of r and 2 r - 2
What is a variable?A variable represents an unknown value.
1) 3 + ___ = 11
2) 6 + = 8
3) 8 + x = 10
4) 5 + = 9
These are all variables
Variable Expressions
Example Meaning Operation
7x 7 times x multiplicationw
10w divided by 10 division
8 p 8 plus p addition
k 5 k minus 5 subtraction
Variable expressions consist of constants,variables, and operations.
Evaluate Evaluate means to find the value of an
algebraic expression by substituting numbers in for variables.
m = 28 + m ?8 + 2 10
Variable SubstitutionEvaluate the variable expression when n = 6.
1) n 8 2) n 26 8
14
6 24
Substitute. Chunk. Use OOO and PEMDAS to complete
Do on whiteboards!
Variable SubstitutionEvaluate the variable expression when n = 6.
3) 3n 4) n6
3 6
1866
1
Substitute. Chunk. Use OOO and PEMDAS to complete
Variable SubstitutionEvaluate the variable expression if a = 3 and b = 4.
1) 6a b 2) a 2b6 43
18 414
3 42 3 8
11
Substitute. Chunk. Use OOO and PEMDAS to complete
Variable SubstitutionEvaluate the variable expression if a = 3 and b = 4.
5) 6ba
6) 5b a
63
4
243
8
5 34
20 3
17
Variable SubstitutionEvaluate the expression if x = 3 and y = 4.
1) 2)2 2x y 26 x y 1 2 23 4
9 16
25
26 (3 14 ) 26 3(5)26 15
11
Take Out Your Learning Targets!!!
An expression is NOT an equation because it does not have an equal sign.
NUMERICAL EXPRESSION: Contains only numbers and symbols. Example: 5 3 + 4
ALGEBRAIC EXPRESSION: Contains numbers, symbols, and variables. Example: m + 8
A VARIABLE is a letter or symbol that represents a number. Example: x
TYPES OF EXPRESSIONS LT #2
Example Problem: Evaluate
4x – 5 + 2(y – 3)
Show the substitution4(2) – 5 + 2(4 – 3)
Chunk it4(2) – 5 + 2(4 – 3)
When x = 2 and y = 4
5 Work down. No equal signs.
8 – 5 + 2(1) Work within each chunk.
3 + 2 Add/Subtract chunks from left to right.
8 – 5 + __2___ Work within each chunk.
LT #2