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Holt McDougal Algebra 1
6-3 Polynomials6-3 Polynomials
Holt Algebra 1
Warm UpWarm Up
Lesson PresentationLesson Presentation
Lesson QuizLesson Quiz
Holt McDougal Algebra 1
Holt McDougal Algebra 1
6-3 Polynomials
Warm UpEvaluate each expression for the given value of x.
1. 2x + 3; x = 2 2. x2 + 4; x = –3
3. –4x – 2; x = –1 4. 7x2 + 2x; x = 3
Identify the coefficient in each term.
5. 4x3 6. y3
7. 2n7 8. –s4
7 13
2 69
4 1
2 –5
Holt McDougal Algebra 1
6-3 Polynomials
Classify polynomials and write polynomials in standard form. Evaluate polynomial expressions.
Objectives
Holt McDougal Algebra 1
6-3 Polynomials
monomialdegree of a monomialpolynomialdegree of a polynomialstandard form of a polynomialleading coefficient
Vocabulary
binomialtrinomial
quadraticcubic
Holt McDougal Algebra 1
6-3 Polynomials
A monomial is a number, a variable, or a product of numbers and variables with whole-number exponents.
The degree of a monomial is the sum of the exponents of the variables. A constant has degree 0.
Holt McDougal Algebra 1
6-3 Polynomials
Example 1: Finding the Degree of a Monomial
Find the degree of each monomial.
A. 4p4q3
The degree is 7. Add the exponents of the variables: 4 + 3 = 7.
B. 7ed
The degree is 2. Add the exponents of the variables: 1+ 1 = 2.C. 3
The degree is 0. Add the exponents of the variables: 0 = 0.
Holt McDougal Algebra 1
6-3 Polynomials
The terms of an expression are the parts being added or subtracted. See Lesson 1-7.
Remember!
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 1
Find the degree of each monomial.
a. 1.5k2m
The degree is 3. Add the exponents of the variables: 2 + 1 = 3.
b. 4x
The degree is 1. Add the exponents of the variables: 1 = 1.
c. 2c3
The degree is 3. Add the exponents of the variables: 3 = 3.
Holt McDougal Algebra 1
6-3 Polynomials
A polynomial is a monomial or a sum or difference of monomials.
The degree of a polynomial is the degree of the term with the greatest degree.
Holt McDougal Algebra 1
6-3 Polynomials
Find the degree of each polynomial.
Example 2: Finding the Degree of a Polynomial
A. 11x7 + 3x3
11x7: degree 7 3x3: degree 3
The degree of the polynomial is the greatest degree, 7.
Find the degree of each term.
B.
Find the degree of each term.
The degree of the polynomial is the greatest degree, 4.
:degree 3 :degree 4
–5: degree 0
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 2
Find the degree of each polynomial.
a. 5x – 6
5x: degree 1Find the degree of
each term.The degree of the polynomial is the greatest degree, 1.
b. x3y2 + x2y3 – x4 + 2
x3y2: degree 5
The degree of the polynomial is the greatest degree, 5.
Find the degree of each term.
–6: degree 0
x2y3: degree 5–x4: degree 4 2: degree 0
Holt McDougal Algebra 1
6-3 Polynomials
The terms of a polynomial may be written in any order. However, polynomials that contain only one variable are usually written in standard form.
The standard form of a polynomial that contains one variable is written with the terms in order from greatest degree to least degree. When written in standard form, the coefficient of the first term is called the leading coefficient.
Holt McDougal Algebra 1
6-3 Polynomials
Write the polynomial in standard form. Then give the leading coefficient.
Example 3A: Writing Polynomials in Standard Form
6x – 7x5 + 4x2 + 9
Find the degree of each term. Then arrange them in descending order:
6x – 7x5 + 4x2 + 9 –7x5 + 4x2 + 6x + 9
Degree 1 5 2 0 5 2 1 0
–7x5 + 4x2 + 6x + 9.The standard form is The leading coefficient is –7.
Holt McDougal Algebra 1
6-3 Polynomials
Write the polynomial in standard form. Then give the leading coefficient.
Example 3B: Writing Polynomials in Standard Form
Find the degree of each term. Then arrange them in descending order:
y2 + y6 – 3y
y2 + y6 – 3y y6 + y2 – 3y
Degree 2 6 1 2 16
The standard form is The leading coefficient is 1.
y6 + y2 – 3y.
Holt McDougal Algebra 1
6-3 Polynomials
A variable written without a coefficient has a coefficient of 1.
Remember!
y5 = 1y5
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 3a
Write the polynomial in standard form. Then give the leading coefficient.
16 – 4x2 + x5 + 9x3
Find the degree of each term. Then arrange them in descending order:
16 – 4x2 + x5 + 9x3 x5 + 9x3 – 4x2 + 16
Degree 0 2 5 3 0235
The standard form is The leading coefficient is 1.
x5 + 9x3 – 4x2 + 16.
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 3b
Write the polynomial in standard form. Then give the leading coefficient.
Find the degree of each term. Then arrange them in descending order:
18y5 – 3y8 + 14y
18y5 – 3y8 + 14y –3y8 + 18y5 + 14y
Degree 5 8 1 8 5 1
The standard form is The leading coefficient is –3.
–3y8 + 18y5 + 14y.
Holt McDougal Algebra 1
6-3 Polynomials
Some polynomials have special names based on their degree and the number of terms they have.
Degree Name
0
1
2
Constant
Linear
Quadratic
3
4
5
6 or more 6th,7th,degree and so on
Cubic
Quartic
Quintic
NameTerms
Monomial
Binomial
Trinomial
Polynomial4 or more
1
2
3
Holt McDougal Algebra 1
6-3 Polynomials
Classify each polynomial according to its degree and number of terms.
Example 4: Classifying Polynomials
A. 5n3 + 4nDegree 3 Terms 2
5n3 + 4n is a cubic binomial.
B. 4y6 – 5y3 + 2y – 9
Degree 6 Terms 4
4y6 – 5y3 + 2y – 9 is a
6th-degree polynomial.
C. –2xDegree 1 Terms 1
–2x is a linear monomial.
Holt McDougal Algebra 1
6-3 Polynomials
Classify each polynomial according to its degree and number of terms.
Check It Out! Example 4
a. x3 + x2 – x + 2Degree 3 Terms 4
x3 + x2 – x + 2 is a cubic polynomial.
b. 6
Degree 0 Terms 1 6 is a constant monomial.
c. –3y8 + 18y5 + 14yDegree 8 Terms 3
–3y8 + 18y5 + 14y is an 8th-degree trinomial.
Holt McDougal Algebra 1
6-3 Polynomials
A tourist accidentally drops her lip balm off the Golden Gate Bridge. The bridge is 220 feet from the water of the bay. The height of the lip balm is given by the polynomial –16t2 + 220, where t is time in seconds. How far above the water will the lip balm be after 3 seconds?
Example 5: Application
Substitute the time for t to find the lip balm’s height. –16t2 + 220
–16(3)2 + 220 The time is 3 seconds.
–16(9) + 220Evaluate the polynomial by using
the order of operations.–144 + 22076
Holt McDougal Algebra 1
6-3 Polynomials
A tourist accidentally drops her lip balm off the Golden Gate Bridge. The bridge is 220 feet from the water of the bay. The height of the lip balm is given by the polynomial –16t2 + 220, where t is time in seconds. How far above the water will the lip balm be after 3 seconds?
Example 5: Application Continued
After 3 seconds the lip balm will be 76 feet from the water.
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 5 What if…? Another firework with a 5-second fuse is launched from the same platform at a speed of 400 feet per second. Its height is given by –16t2 +400t + 6. How high will this firework be when it explodes?
Substitute the time t to find the firework’s height.
–16t2 + 400t + 6
–16(5)2 + 400(5) + 6 The time is 5 seconds.
–16(25) + 400(5) + 6
–400 + 2000 + 6 Evaluate the polynomial by using the order of operations.
–400 + 20061606
Holt McDougal Algebra 1
6-3 Polynomials
Check It Out! Example 5 Continued
What if…? Another firework with a 5-second fuse is launched from the same platform at a speed of 400 feet per second. Its height is given by –16t2 +400t + 6. How high will this firework be when it explodes?
When the firework explodes, it will be 1606 feet above the ground.
Holt McDougal Algebra 1
6-3 Polynomials
Lesson Quiz: Part I
Find the degree of each polynomial.
1. 7a3b2 – 2a4 + 4b – 15
2. 25x2 – 3x4
Write each polynomial in standard form. Then
give the leading coefficient.
3. 24g3 + 10 + 7g5 – g2
4. 14 – x4 + 3x2
4
5
–x4 + 3x2 + 14; –1
7g5 + 24g3 – g2 + 10; 7
Holt McDougal Algebra 1
6-3 Polynomials
Lesson Quiz: Part II
Classify each polynomial according to its degree and number of terms.
5. 18x2 – 12x + 5 quadratic trinomial
6. 2x4 – 1 quartic binomial
7. The polynomial 3.675v + 0.096v2 is used to estimate the stopping distance in feet for a car whose speed is v miles per hour on flat dry pavement. What is the stopping distance for a car traveling at 70 miles per hour? 727.65 ft
Holt Algebra 1
6-4 Adding and Subtracting Polynomials6-4 Adding and Subtracting Polynomials
Holt Algebra 1
Warm UpWarm Up
Lesson PresentationLesson Presentation
Lesson QuizLesson Quiz
Holt McDougal Algebra 1
Holt McDougal Algebra 1
6-3 Polynomials
Warm UpSimplify each expression by combining like terms.
1. 4x + 2x
2. 3y + 7y
3. 8p – 5p
4. 5n + 6n2
Simplify each expression.
5. 3(x + 4)
6. –2(t + 3)
7. –1(x2 – 4x – 6)
6x
10y
3p
not like terms
3x + 12
–2t – 6
–x2 + 4x + 6
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add and subtract polynomials.
Objective
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Just as you can perform operations on numbers, you can perform operations on polynomials. To add or subtract polynomials, combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add or subtract.
Example 1: Adding and Subtracting Monomials
A. 12p3 + 11p2 + 8p3
12p3 + 11p2 + 8p3
12p3 + 8p3 + 11p2
20p3 + 11p2
Identify like terms.Rearrange terms so that like
terms are together.Combine like terms.
B. 5x2 – 6 – 3x + 8
5x2 – 6 – 3x + 8
5x2 – 3x + 8 – 6
5x2 – 3x + 2
Identify like terms.Rearrange terms so that like
terms are together.Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add or subtract.
Example 1: Adding and Subtracting Monomials
C. t2 + 2s2 – 4t2 – s2
t2 – 4t2 + 2s2 – s2
t2 + 2s2 – 4t2 – s2
–3t2 + s2
Identify like terms.Rearrange terms so that
like terms are together.Combine like terms.
D. 10m2n + 4m2n – 8m2n
10m2n + 4m2n – 8m2n
6m2n
Identify like terms.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Like terms are constants or terms with the same variable(s) raised to the same power(s). To review combining like terms, see lesson 1-7.
Remember!
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Check It Out! Example 1
a. 2s2 + 3s2 + s
Add or subtract.
2s2 + 3s2 + s
5s2 + s
b. 4z4 – 8 + 16z4 + 2
4z4 – 8 + 16z4 + 2
4z4 + 16z4 – 8 + 2
20z4 – 6
Identify like terms.
Combine like terms.
Identify like terms.Rearrange terms so that
like terms are together.Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Check It Out! Example 1
c. 2x8 + 7y8 – x8 – y8
Add or subtract.
2x8 + 7y8 – x8 – y8
2x8 – x8 + 7y8 – y8
x8 + 6y8
d. 9b3c2 + 5b3c2 – 13b3c2
9b3c2 + 5b3c2 – 13b3c2
b3c2
Identify like terms.
Combine like terms.
Identify like terms.Rearrange terms so that
like terms are together.Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Polynomials can be added in either vertical or horizontal form.
In vertical form, align the like terms and add:
In horizontal form, use the Associative and Commutative Properties to regroup and combine like terms.
(5x2 + 4x + 1) + (2x2 + 5x + 2)
= (5x2 + 2x2) + (4x + 5x) + (1 + 2)
= 7x2 + 9x + 3
5x2 + 4x + 1+ 2x2 + 5x + 2
7x2 + 9x + 3
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add.
Example 2: Adding Polynomials
A. (4m2 + 5) + (m2 – m + 6)
(4m2 + 5) + (m2 – m + 6)
(4m2 + m2) + (–m) +(5 + 6)
5m2 – m + 11
Identify like terms.
Group like terms together.
Combine like terms.
B. (10xy + x) + (–3xy + y)
(10xy + x) + (–3xy + y)
(10xy – 3xy) + x + y
7xy + x + y
Identify like terms.
Group like terms together.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add.
Example 2C: Adding Polynomials
(6x2 – 4y) + (3x2 + 3y – 8x2 – 2y)
Identify like terms.
Combine like terms in the second polynomial.
Combine like terms.
(6x2 – 4y) + (3x2 + 3y – 8x2 – 2y)
(6x2 – 4y) + (–5x2 + y)
(6x2 –5x2) + (–4y + y)
x2 – 3ySimplify.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Add.
Example 2D: Adding Polynomials
Identify like terms.
Group like terms together.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Check It Out! Example 2
Add (5a3 + 3a2 – 6a + 12a2) + (7a3 – 10a).
(5a3 + 3a2 – 6a + 12a2) + (7a3 – 10a)
(5a3 + 7a3) + (3a2 + 12a2) + (–10a – 6a)
12a3 + 15a2 – 16a
Identify like terms.
Group like terms together.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
To subtract polynomials, remember that subtracting is the same as adding the opposite. To find the opposite of a polynomial, you must write the opposite of each term in the polynomial:
–(2x3 – 3x + 7)= –2x3 + 3x – 7
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Subtract.
Example 3A: Subtracting Polynomials
(x3 + 4y) – (2x3)
(x3 + 4y) + (–2x3)
(x3 + 4y) + (–2x3)
(x3 – 2x3) + 4y
–x3 + 4y
Rewrite subtraction as addition of the opposite.
Identify like terms.
Group like terms together.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Subtract.
Example 3B: Subtracting Polynomials
(7m4 – 2m2) – (5m4 – 5m2 + 8)
(7m4 – 2m2) + (–5m4 + 5m2 – 8)
(7m4 – 5m4) + (–2m2 + 5m2) – 8
(7m4 – 2m2) + (–5m4 + 5m2 – 8)
2m4 + 3m2 – 8
Rewrite subtraction as addition of the opposite.
Identify like terms.
Group like terms together.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Subtract.
Example 3C: Subtracting Polynomials
(–10x2 – 3x + 7) – (x2 – 9)
(–10x2 – 3x + 7) + (–x2 + 9)
(–10x2 – 3x + 7) + (–x2 + 9)
–10x2 – 3x + 7–x2 + 0x + 9
–11x2 – 3x + 16
Rewrite subtraction as addition of the opposite.
Identify like terms.
Use the vertical method.Write 0x as a placeholder.Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Subtract.
Example 3D: Subtracting Polynomials
(9q2 – 3q) – (q2 – 5)
(9q2 – 3q) + (–q2 + 5)
(9q2 – 3q) + (–q2 + 5)
9q2 – 3q + 0+ − q2 – 0q + 5
8q2 – 3q + 5
Rewrite subtraction as addition of the opposite.
Identify like terms.Use the vertical method.Write 0 and 0q as
placeholders.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Check It Out! Example 3
Subtract.
(2x2 – 3x2 + 1) – (x2 + x + 1)
(2x2 – 3x2 + 1) + (–x2 – x – 1)
(2x2 – 3x2 + 1) + (–x2 – x – 1)
–x2 + 0x + 1 + –x2 – x – 1–2x2 – x
Rewrite subtraction as addition of the opposite.
Identify like terms.
Use the vertical method.Write 0x as a placeholder.
Combine like terms.
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
A farmer must add the areas of two plots of land to determine the amount of seed to plant. The area of plot A can be represented by 3x2 + 7x – 5 and the area of plot B can be represented by 5x2 – 4x + 11. Write a polynomial that represents the total area of both plots of land.
Example 4: Application
(3x2 + 7x – 5)(5x2 – 4x + 11)
8x2 + 3x + 6
Plot A.Plot B.
Combine like terms.
+
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Check It Out! Example 4
The profits of two different manufacturing plants can be modeled as shown, where x is the number of units produced at each plant.
Use the information above to write a polynomial that represents the total profits from both plants.
–0.03x2 + 25x – 1500 Eastern plant profit.
–0.02x2 + 21x – 1700 Southern plant profit.Combine like terms.
+–0.05x2 + 46x – 3200
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Lesson Quiz: Part I
Add or subtract.
1. 7m2 + 3m + 4m2
2. (r2 + s2) – (5r2 + 4s2)
3. (10pq + 3p) + (2pq – 5p + 6pq)
4. (14d2 – 8) + (6d2 – 2d +1)
(–4r2 – 3s2)
11m2 + 3m
18pq – 2p
20d2 – 2d – 7
5. (2.5ab + 14b) – (–1.5ab + 4b) 4ab + 10b
Holt Algebra 1
6-4 Adding and Subtracting Polynomials
Lesson Quiz: Part II
6. A painter must add the areas of two walls to determine the amount of paint needed. The area of the first wall is modeled by 4x2 + 12x + 9, and the area of the second wall is modeled by
36x2 – 12x + 1. Write a polynomial that represents the total area of the two walls.
40x2 + 10