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Week 2: POLYNOMIALSSAT Prep
I. POLYNOMIALS
A.) Vocabulary
Monomials – Any number or variable or product of number(s) and variable(s)
Ex. Evaluate when a = -4 and b = 0.5.
23a b
23 4 0.5 3 16 0.5 24
B.) Simplifying Polynomials
!!** ADD OR SUBTRACT LIKE TERMS ONLY **!!
Like terms – same variable(s) and same exponent(s).
Ex. Simplify
2 23 4 2 5 . x x x x
2 23 2 4 5 x x x x 25 9x x
Binomials – 2 monos separated by +/-
Trinomials – 3 monos separated by +/-
2 3x
22 3 1 x x
Multiplying Monomials - Mult. Coeffecients and add exponents of like bases
Ex. Simplify the following:
2 3 2(3 )( 2 )xy z x y
2 2 33 2 x x y y z 3 3 36 x y z
Dividing Monomials- Div. coeff. And subtract exponents of like bases
Ex. Simplify the following:
4 2 3
2
(6 )
( 2 )
x y z
x z
4 2 3
2
6
2 1
x y z
x z
4 2 2 3 13
1 1 1 1
x y z
2 2 23 x y z
C.) Factoring and Expanding
FOIL – First Outer Inner Last
Ex . Expand the following:
3 3 7 x x
FIRST:
3x x
23 2 21 x x
OUTER: INNER: LAST:
7x 3 3x 3 7
23x 7 x 9 x 21
Three important binomial products
2 2
2 2 2
2 2 2
( )( )
( ) 2
( ) 2
x y x y x y
x y x xy y
x y x xy y
Ex. If (a – b) = 17.5 and (a + b) = 10, what does a2 – b2 =?
Ex. If x2 + y2 = 36 and (x + y) 2 = 64 what is xy?
2 2a b a b a b
175 2 2 17.5 10a b
2 2 22x y x xy y
2 264 2x xy y
28 2xy
64 2 36xy
14xy
D.) MORE FACTORING GCF, Common Monomials, and Product/sum table
Ex. Find all real solutions of
2 6 0x x
FACTORS (-6) SUM (-1)
1,6
1, 62,3
2, 3
5
5
11
2 3 0 x x
2 0 or 3 0 x x
2 or 3 x x
Ex. Find an equivalent expression for
Ex. Find the sum of reciprocals of
2
2
3 4
4 4
x
x x
2
2
3 12.
4 4
x
x x
2 2
1 1 and .
x y
3 2 2
2 2
x x
x x
3 2
2
x
x
2 2+ x y
A.) Single Equations
Ex. Solve the following for x:
II. EQUATIONS and INEQUALITIES
13( 2) 2( 1) 1
2x x x
13 6 2 2 1
2 x x x
12 3 6 2 3
2 x x x
6 12 4 6 x x x
7 12 4 6 x x
3 18x
6x
Ex. If a = b(c + d), solve for d in terms of a, b, and c.
Ex. If , then x = ?
3 1 5 x
3 6x
a bc bd
a bc bd
a bcd
b
or a bc a
d d cb b
2x
2 2
2x
4x
Ex. If 2x – 5 = 98, then 2x + 5 = ?
Ex. For what value of x is ? 10
2 5 2 5 10 x x
4 3 10
5
x x
2 5 98 10 x 108
3 6
5x
3 30x
Ex. If , solve for x.
Ex. If , then x = ?
25 3 y x
2 4 125 x
11x
23 5 y x
23
5
yx 3
5
yx
2 121x
2 121x
Ex. Find the largest value of x that satisfies .
Ex. If , what is w?
22 3 0 x x
2 3 0 x x
0 or 2 3 0 x x 3
2x
3 14 8 w w
3 12 32 2
w w
2 3 3 12 2 w w
2 3 3 1 w w
2 6 3 3 w w
9w
B.) Systems of Equations/Inequalities
Use appropriate method Substitution, elimination, graphing, matrices
Ex. Solve for x and y if x + y = 10 and x – y = 2.
10
2
x y
x y
2 12x
6x
6 10 y
4y
6,4
Ex. If 3a + 5b = 10 and 5a + 3b = 30, what is the average of a and b?
3 5 10
5 3 30
a b
a b
8
5
2
8 8 40 a b
5 a b
5
2 2
a b
III. WORD PROBLEMS
READ, READ, READ, READ, and READ AGAIN!!!
A.) Strategies
1.) Substitution i.e., “Plugging it in”
Why???- Numbers make more sense than letters.- Choose numbers easy to work with, but not 0 and 1.- 2,3,5, etc. are good choices for algebra problems.- Multiples of 100 for percent problems.- Multiples of 60 for time problems.
When??? -You have NO idea how to do the problem-There is a variable in the question and the answers are all numbers-The problem is about “some number” and you have no clue as to what that number is.
B.) Examples Ex. The price of an item in a store is d dollars. If the sales tax on the item is s%, what is the total cost of x such items, including tax?
a.)
b.)
c.)
d.)
e.)
1
100
xd s
100 ( )x d ds
( 100)
100
xd s
1xds
xds
Let’s choose some numbers for d, s, and x. The total price for 1 item =
The total price for 10 items =
Which choice gives us $105.00? – Start with A
Obviously, B.) is out
10
5%
10
d
s
x
10 10(.05) $10.50
10 $10.50 $105.00
xds 10 10 5 500 NO
C.) D.)
E.)
100 ( )x d ds
10 10 5 16
100
1
100
xd s NO
100 10 10 10 5 25000 NO
( 100)
100
xd s 10 10 (5 100)105
100
YES!!!
Ex. Vehicle A travels at x miles per hour for x hours. Vehicle B travels a miles faster than Vehicle A, and travels b hours longer than Vehicle A. Vehicle B travels how much farther than Vehicle A, in miles?
a.)
b.)
c.)
d.)
e.)
ax bx ab
2x abx ab
22x a b x ab
2x ab
2 2a b
Let’s choose some numbers for x, a, and b. Vehicle A =
Vehicle B =
Vehicle B – Vehicle A =
By substitution – A.)
20
10
5
x
a
b
20 20 400
220 10(5) 350 2x ab
30 25 750
750 400 350
The End!!!