Chapter 9: Polynomials and Factoring
Introduction
This chapter will present a new type of function: the polynomial. Chances are, polynomials will be new to you. However, polynomials are used in many careers and real life situations  to model the population of a city over a century, to predict the price of gasoline, and to predict the volume of a solid. This chapter will also present basic factoring  breaking a polynomial into its linear factors. This will help you solve many quadratic equations found in Chapter 10.
 9.1.
Polynomials in Standard Form
 9.2.
Addition and Subtraction of Polynomials
 9.3.
Multiplication of Monomials by Polynomials
 9.4.
Multiplication of Polynomials by Binomials
 9.5.
Special Products of Polynomials
 9.6.
Monomial Factors of Polynomials
 9.7.
Zero Product Principle
 9.8.
Factorization of Quadratic Expressions
 9.9.
Factor Polynomials Using Special Products
 9.10.
Factoring by Grouping
 9.11.
Factoring Completely
 9.12.
Probability of Compound Events
Chapter Summary
Summary
This chapter first deals with polynomials. It starts by talking about how to classify, simplify, and rewrite polynomials in standard form, and it then moves on to discuss the adding and subtracting of polynomials. Next, instruction is given on multiplying a polynomial by a monomial, multiplying a polynomial by a binomial, and finding special products of polynomials. The chapter then provides a great deal of information on factors and factoring, including monomial factors of polynomials, factorization of quadratic expressions, using special products to factor, factoring by grouping, and factoring completely. Solving polynomial equations using the Zero Product Principle is also touched upon. Finally, the probability of compound events is introduced.
Polynomials and Factoring; More on Probability Review
Define the following words:
 Polynomial
 Monomial
 Trinomial
 Binomial
 Coefficient
 Independent events
 Factors
 Factoring
 Greatest common factor
 Constant
 Mutually exclusive
 Dependent events
Identify the coefficients, constants, and the polynomial degrees in each of the following polynomials.

x5−3x3+4x2−5x+7 
x4−3x3y2+8x−12
Rewrite the following in standard form.

−4b+4+b2 
3x2+5x4−2x+9
Add or subtract the following polynomials and simplify.
 Add
x2−2xy+y2 and2y2−4x2 and10xy+y3 .  Subtract
x3−3x2+8x+12 from4x2+5x−9 .  Add
2x3+3x2y+2y andx3−2x2y+3y
Multiply and simplify the following polynomials.

(−3y4)(2y2) 
−7a2bc3(5a2−3b2−9c2) 
−7y(4y2−2y+1) 
(3x2+2x−5)(2x−3) 
(x2−9)(4x4+5x2−2) 
(2x3+7)(2x3−7)
Square the binomials and simplify.

(x2+4)2 
(5x−2y)2 
(13x2+2y)
Solve the following polynomial equations.

4x(x+6)(4x−9)=0 
x(5x−4)=0
Factor out the greatest common factor of each expression

−12n+28n+4 
45x10+45x7+18x4 
−16y5−8y5x2+40y6x3 
15u4−10u6−10u3v 
−6a9+20a4b+10a3 
12x+27y2−27x6
Factor the difference of squares.

x2−100 
x2−1 
16x2−25 
4x2−81
Factor the following expressions completely.

5n2+25n 
7r2+37r+36 
4v2+36v 
336xy−288x2+294y−252x 
10xy−25x+8y−20
Complete the following problems.
 One leg of a right triangle is 3 feet longer than the other leg. The hypotenuse is 15 feet. Find the dimensions of the right triangle.
 A rectangle has sides of
x+5 andx−3 . What value ofx gives an area of 48?  Are these two events mutually exclusive, mutually inclusive, or neither? “Choosing the sports section from a newspaper” and “choosing the times list for a movie theater”
 You spin a spinner with seven equal sections numbered one through seven and roll a sixsided cube. What is the probability that you roll a five on both the cube and the spinner?
 You spin a spinner with seven equal sections numbered one through seven and roll a sixsided cube. Are these events mutually exclusive?
 You spin a spinner with seven equal sections numbered one through seven and roll a sixsided cube. Are these events independent?
 You spin a spinner with seven equal sections numbered one through seven and roll a sixsided cube. What is the probability you spin a 3, 4, or 5 on the spinner or roll a 2 on the cube?
Polynomials and Factoring; More on Probability Test
Simplify the following expressions.

(4x2+5x+1)−(2x2−x−3) 
(2x+5)−(x2+3x−4) 
(b+4c)+(6b+2c+3d) 
(5x2+3x+3)+(3x2−6x+4) 
(3x+4)(x−5) 
(9x2+2)(x−3) 
(4x+3)(8x2+2x+7)
Factor the following expressions.

27x2−18x+3 
9n2−100 
648x2−32  \begin{align*}81p^290p+25\end{align*}
 \begin{align*}6x^235x+49\end{align*}
Solve the following problems.
 A rectangle has sides of \begin{align*}x+7\end{align*} and \begin{align*}x5\end{align*}. What value of \begin{align*}x\end{align*} gives an area of 63?
 The product of two positive numbers is 50. Find the two numbers if one of the numbers is 6 more than the other.
 Give an example of two independent events. Determine the probability of each event. Use it to find:
 \begin{align*}P(A \cup B)\end{align*}
 \begin{align*}P(A \cap B)\end{align*}
 The probability it will rain on any given day in Seattle is 45%. Find the probability that:
 It will rain three days in a row.
 It will rain one day, not the next, and rain again on the third day.
Texas Instruments Resources
In the CK12 Texas Instruments Algebra I FlexBook, there are graphing calculator activities designed to supplement the objectives for some of the lessons in this chapter. See http://www.ck12.org/flexr/chapter/9619.