Unit 1 Foundations of Algebra

Transcription

1 1 Unit 1 Foundations of Algebra

2 Real Number System 2 A. Real Number System 1. Counting Numbers (Natural Numbers) {1,2,3,4, } 2. Whole Numbers { 0,1,2,3,4, } 3. Integers - Negative and Positive Whole Numbers { -2,-1,0,1,2,..} 4. Rational - Any number that can be written as a fraction a where b 0 EX: -2, ½, 5.46, b perfect, Irrational - A non-repeating, non-terminating decimal EX: π, non perfect 6. Real All Rational and Irrational Numbers B. Types of Sets and Numbers Finite- a set that ends Infinite - a set that doesn t end or terminate Absolute Value the distance a number is from zero Prime Numbers exactly 2 factors {2,3,5 } Composite Numbers- more than 2 factors {4,6,8,9 } (One and Zero are neither prime/composite) Even {0,2,4,6,.} Odd {1,3,5,7 } Inequalities - >,, <,

3 Real Number System 3

4 4 Real Number System Simplify and then identify each of the following as rational or irrational π 1 π 20. Given the list of numbers below, determine which number sets they belong to. 3 5,, 0.5, 4, π 2 a) Integers b) Rational c) Irrational

5 Properties/Closure 5 A. Closure A set is closed (under an operation) if and only if the operation on two elements of the set produces another element of the set. If an element outside the set is produced, then the operation is not closed The round smiley faces are a closed set. No matter what operation is performed on round smiley faces, another round smiley face will be created. Thus, there are always only round smiley faces in the box. 1) Is the set of whole numbers closed under addition? - Add any two whole numbers - Will the sum still be a whole number? - Will any sum of 2 whole numbers still be a whole number? If yes It is CLOSED Whole Numbers If no It is NOT CLOSED * Always think about a closed circle 2) Is the set of whole numbers closed under subtraction? 3) Is the set of whole numbers closed under multiplication? 4) Is the set of whole numbers closed under division? 5) Is the set {0,1} Closed under a) addition? b) Subtraction? c) Multiplication d) Division? Under which operations is the set {odd integers} closed?

6 Properties/Closure 6 B. Properties Examples: What property is illustrated by each statement? 1) = -42 2) (x + 2.5) + 28 = x + ( ) 3) 10x + 0 = 10x 4) 4x 1 = 4x 5) x + ( y + z) = (x + y ) + z 6) (3 + 4) + 5 = (4 + 3) + 5

7 Properties/Closure 7 C. Inverses Find the additive and multiplicative inverse of each Example Additive Inverse Multiplicative inverse -5 ½ 5.2-3/4 2 6/7 8

8 Properties/Closure 8 18) For which of the following numbers: 2, 3, 4, 5, 6 is the expression x + 2 closed? 19) Which of the following is a rational number? A) B) π C) 15 D) 9 8

9 Properties/Closure 9 Choose the best answer: 1) Which of the following is an integer, but not a whole number? A) 0 B) -11 C) -1/2 D) ) Which of the following is not a counting number (natural number)? A) 0 B) 1 C) 2 D) 3 9) Which of the following is not a rational number? 1 A) 6 B) C) 7π D) ) Which of the following is a rational number? A) B) π C) 15 D) 9 8 3) Which is an example of a whole number? A) 0 B) -11 C) 2.5 D) ) Which of the following is not an irrational number? π A) 4 B) C) 7 D) ) Which number is an integer, a whole number, and a counting (natural) number? A) 0 B) -1 C) 15 D) 0.5 5) Which of the following is a rational number? A) π B) 11 C) 2 D) ) Which of the following is irrational? 1 A) 0 B) 2 C) 2π D) ) Which of the following is an example of a non-perfect square? A) 9 B) 81 C) 225 D) 45 8) What is the first counting (natural) number? 12) Which of the following is an irrational number? A) 9.5 B) 3.14 C) 9π D) ) 197 lies between which two consecutive integers? A) 196 & 197 B) 14 & 15 C) 15 & 16 D) 197 & ) Jessica is asked if 5π is a rational number. Which of the following is the most logical response? A) No, it is irrational because any multiple of π is irrational. B) Yes, it is rational because 5π can be written as a fraction. C) No, it is irrational because 5 is a prime number. D) Yes, it is rational because 5 and π are both rational. A) 0 B) 1 C) -1 D) 0.1

10 Properties/Closure 10 15) Which letter on the number line below best represents the value of 6? A B C D ) Place the following numbers on the number line: 5, 3 2, 0.5, 4, π ) Harry is asked if 100 is a rational number. He answers No, it is irrational because the square root of any number is irrational. Is Harry correct? Explain why he is or is not correct. Tell whether each description is rational or irrational: 18) Terminating decimals are. 19) Pi is 20) Fractions are. 21) The square roots of perfect squares are. 22) The square roots of all other positive integers are. 23) Decimals that repeat with a pattern are. 24) Change 4 5 to a decimal. Is that rational or irrational? 25) Change 22 7 to a decimal. Is that rational or irrational? 26) Is 3.14 rational or irrational?

11 Numerical Expressions/Evaluating Expressions Warm Up: (3)(-5)(-2) A. Operations with Integers (-4) (-4)(-35+7) 10. 3(-6)(2) 11. ( 3) 2 B. Simplifying Expressions Order of Operations Simplify (4+3) (4 3) (5-1) (5 2 10) (4) 9 6 C. Expression vs. Equation D. Evaluate

12 12 Numerical Expressions/Evaluating Expressions x for x=7 2. 2x 2 5x 4 a) for x=7 3. 2a (n 1)d 5 for a= -4 b) for x= -7 n=10 d=3 4. x 3 ; x x 2 ; x 4 What is the value of the expression for x = -5 and y = 2 6) x 2 + x - 12 y 2 7) (xy) 2 x 2 y What is the value of the expression for a = 3 and b = -4 8) (a) (b) 9) 3b a 2 10) 2b 2-7a

13 13 Simplifying Expressions Warm Up: 1. Which of the following is the set of negative integers greater than -3? (1) {-4,-5,-6,-7 } (2) {-3,-4,-5,-6 } (3) {-3,-2,-1} (4) {-2,-1} 2. The exact value of the rational number 5/3 can be written as (1) 1.6 (2) 1.6 (3) (4) Which of the following numbers is rational? (1) (2) 2 (3) 1.42 (4) Which of the following inequalities is a true statement? (1).026<0.25<0.2 (2) 0.2<.026<0.25 (3) 0.2<0.25<0.026 (4) 0.026<0.2< Which of the following is a correct application of the distributive property? (1) 4(8+0.2) = 4(8)+4(0.2) (3) 8(5+4)=8(5)+4 (2) 6(3-1)=6(-1+3) (4) 8(5)(4)=8(5)+8(4) 6. The additive inverse of 7 is (1) -7 (2) 0 (3) 1/7 (4) 7 7. Which set of number is closed under subtraction? (1) counting numbers (2) whole numbers (3) integers (4) odd numbers 8. Which set of number is not closed under multiplication? (1) counting numbers (2) negative integers (3) even integers (4) rational numbers 9. The set of integers is not closed under which operation? (1) addition (2) subtraction (3) multiplication (4) division A. Vocabulary 4x² 1) Name the variable 2) Name the coefficient 3) Name the exponent 4) Name the base Monomial/Term a number, a variable, the product of a number and variable Examples - 8, 9x, 9xy, -27x²,,, Binomial the sum/difference of 2 different terms Examples - (8x + 9), (3x 4),,,

14 Simplifying Expressions 14 Trinomial - the sum/difference of 3 different terms Examples - (8x + 3y 4),,, Degree of a Term (Monomial) the sum of the variable exponents Degree of the polynomial the highest degree of the monomial terms Standard Form Decending order of exponents Simplest Form no like terms Like Terms same variable raised to the same power B. Combining Like Terms 1) 4t + 6t 2) 17y 15y 3) 11b 2 + 4b 2 4) 12x 2 ( 5x 2 ) 5) 8xy 2 xy 2 6) 6y 6y 7) 2f + 7g 6 + 8g 8) 8x + 3 5x 9 9) 5k 6k 2 12k + 10

15 Simplifying Expressions 15 Geometry Write an expression in simplified form for the perimeter of each rectangle C. Distributive Property 1) 3(x + 8) - x 2) -7(5x 4)+ 7 3) 5(x 7) + 6x 4) 12( 3-1 x) 5) 3( n) 6) 1 (7x + 5) 6 2 Simplify each expression. 11) 2.3 (14 + x) + 2x 12) ( 8 6t) 10(2t 3) 13) (6 + d) + 4d 14) ( r + 1) 15) 1 3z ) m 3 Geometry Write an expression in simplified form for the area of each rectangle

16 Simplifying Expressions Simplify each expression (c + 5) + 4(4c 9) 2. (n 1) + 8n The profit a company receives is given by the expression 0.15(855p 315) where p is the number of products sold. Rewrite this expression using the Distributive Property. What is the profit for 25 products sold. 4. Reasoning Demonstrate why 15x 5 3x 5. Show your work. 5 Simplify each expression (-x + 4) 4x (2n 7y + 4) t) 8. (4x - 7) ( 5 Geometry Write an expression in simplified form for the perimeter and area of each rectangle Express each polynomial in standard form and find the degree of each expression. 11. x 3 + 3x 5x x 2 + 2x x x State the degree of each polynomial

17 Translate Expressions 17 Warm Up: Ditto x + 5 x 5 5x 5 x The sum of x and 5 The difference of x and 5 The product of 5 and x The quotient of 5 and x 5 Multiplied by x 5 Divided by x x plus 5 x Increased by 5 x minus 5 5 More than x x Diminished by 5 Twice x 2x 5 Less than x x squared x 2 5 Subtracted from x The cube of a number x 3 A. Translate 1. W more than 3 2. w less than 3 3. w decreased by 2 4. the product of 5r and x 5. twice x, decreased by , diminished by 4 times n 7. the sum of t and u, divided by decreased by twice (x+5) 9. the distance that is 20 meters shorter than x meters 10. a bill for n baseball caps, each costing d dollars 11. a weight that is 40 pounds heavier than p pounds 12. an amount of money that is twice d dollars 13. Brianna paid 17 dollars for batteries and film for her camera. If the batteries cost x dollars, express the cost of the film in terms of x

18 18 Translate Expressions x + 5 x - 5 5x 5 x A. Translate 1. x more than 3 2. w less than 3 3. w decreased by 2 4. the product of 5r and x 5. twice x, decreased by subtracted from 4 times n

19 Translate Expressions the sum of t and u, divided by decreased by twice (x+5) 10. the distance that is 20 meters shorter than x meters 11. One-eighth π times the cube of the diameter d 12. a weight that is 40 pounds heavier than p pounds 13. an amount of money that is twice d dollars 14. The square root of the sum of the squares of the altitude a and the base b times the quantity of four less than x 16. four less than five times x less than twice the width, w

20 20 Translate Expressions Write an algebraic expression for each word phrase minus f 2. the sum of 11 and k 3. x multiplied by 6 4. a number t divided by 3 5. one fourth of a number n 6. the product of 2.5 and a number t 7. the quotient of 15 and y 8. a number q tripled 9. The difference between the square root of x and π squared. 10. The sum of x and y decreased by their product. 11. The square of r increased by a quantity that is fifty times the cube of k. 12. Twice π divided by the cube of the sum of x and The difference between the square of the hypotenuse h and the square of the altitude a of a triangle 14. Error Analysis A student writes 5y 3 to model the relationship the sum of 5y and 3. Explain the error. 15. Error Analysis A student writes the difference between 15 and the product of 5 and y to describe the expression 5y 15. Explain the error.

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22 Translate Expressions A bike rider is traveling at a speed of 15 feet per second. Write an expression for the distance the rider has traveled after s seconds. 14 a. If the tax that you pay when you purchase an item is 12% of the sale price, write an expression that gives the tax on the item with a price p. Write another expression that gives the total price of the item, including tax. b. Determine the total price, including tax, of an item that costs $ The cost to rent a hall for school functions is $60 per hour. Write an expression for the cost of renting the hall for h hours.

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