Download section 1.2 grouping symbols

ALGEBRA I. NOTES
SECTION 1.2 GROUPING SYMBOLS
In the last section, we worked with parentheses which are a grouping symbol.
Ex.) 5  (16  4)
Work to simplify what’s in the parentheses 1st.
A.) Grouping Symbol – is a device used to enclose an expression that should be
simplified 1st.
Note: Different groupings may produce different numbers.
(15  3)  2
15  (3  2)
There are 3 Grouping Symbols that we will work with:
1.) Parentheses – can be used to represent multiplication.
Ex.) 7(5  3)
2.) Brackets – generally used in expressions that already contain parentheses to make
them easier to read.
Ex.)
6 5  (8  2)
3.) Fraction Bar – grouping symbol as well as a division sign.
53
Ex.)
22
WHAT HAPPENS IF AN EQUATION CONTAINS MORE THAN 1 GROUPING
SYMBOL?
Ex.) 10 3  (2  5)  (3)
Simplify expression in the innermost grouping symbol
Then work toward the outermost.
This brings us to ORDER OF OPERATIONS:
In everyday life, there are situations which require that steps be completed in a certain
order to correctly accomplish a task.
Examples of Situations: 1. Listening to a CD
Same thing happens in Algebra – you need to complete steps in a certain order to get a
correct answer!
Please Excuse My Dear Aunt Sally
P
E
M
D
A
S
Examples:
4x  5 y
3x  y
x  3, y  8
16.)a.) 9xyz  t
16.)b.) 9 x( zy  t )
26.) 3 z  5(2 y  x)
28.) 2t  7 z  ( y  x)
Sample Problems:
14.a.) zt  y
22.)
4 y  2t
y  2t
31.)
1
h (b  c )
2
14.b.) z (t  y )
24.)
2( y  x)
2y  x