Quadratic equations Questions and Answers

In a town whose population is 4000 a disease creates an epidemic The number of people N infected t days after the disease has begun is given by the function 4000 N 1 1 17 16 0 4 Graph the function Find the number of people initially infected and the number infected after 11 days Choose the correct graph OB a Q G All graphs are 0 20 0 5500 Xscl 1 Yscl 500 How many are initially infected with the disease t 0 people Round to nearest integer or whole person Q Q L

Solve the equation and check your solution It is possible that there is NO SOLUTION If y 13 what is the solution x y 0 Type a response

6 Graph f x and g x on the set of axes below f x X x 4x 3 x 1 g x x

Mic 1 Aare pa 2 HAHT 1 P m p ne 8600 325 576 x 42 165 220 480 2 P n e p 5 4a a 6 3 3 11 12 7 8 a 6 6 7 4 2 3 9m 7m m 8 m 16m 64 49 a 27 4 Y 9m 65 8m 64 m 64 5 x 7x 4 0 x m 8 16 2 x 3 12 x x 3 x 3 x 9x 3 x a 3 1 7 15 2 a 27a a 27a 40 a 2 2 a 3a 9 16 a 8 x x 1 x x 1 6 1 4 a

d No the polygon is not regular It is equiangular but it is not equilateral No the polygon is not regular It is neither equilateral nor equiangular 94 94 Yes the polygon is regular It is both equilateral and equiangular No the polygon is not regular It is equilateral but it is not equiangular No the polygon is not regular It is equiangular but it is not equilateral O No the polygon is not regular It is neither equilateral nor equiangular X

59 a Find y if the radius of the circle is 100 feet and 0 30 b Use the information from Part a to find x

a Consider the following 48 Find the value of x in the triangle X 66 acute Classify the triangle in as many ways as possible Select all that apply equiangular equilateral isosceles obtuse to right scalene to b Consider the following

b 36

Use the revenue and cost graphs on the right to find the approximate profit from manufacturing 24 000 cell phones What is the approximate profit from manufacturing 24 000 phones Dollars in millions 5 4 3 2 1 0 8 Revenue 16 Cast 24 32 40 48 o Q G

Problems 15 and 16 refer to Figure 18 A D FIGURE 18 15 Find AB if BC 4 BD 5 and AD 2 16 Find BD if BC 5 AB 13 and AD 2 17 What acute positive angle does the line y B C x make with the positive x axis

K Write the rational expression in lowest terms Z 5z 6 z z 6 z 5z 6 z z 6 2 Simplify your answer

4 4 Ip H y f x X

c Right Select all that apply C B O B

Find and sketch an angle that is complementary to the angle O 90 b Consider the following 45 145 O 45 135

MY NOTES Find the value of x for each polygon X ASK YOUR TEACHER b 120 124 to 158 to 120 128 111 1219 PRACTICE A

4 1 Points DETAILS Sketch an isosceles triangle Need Help Read It Submit Answer LARMPMT1 10 1 021 MY NOTES ASK YOUR TEACHER

2 y f x D

Exercises 111 114 Critical Thinking The graph of a function f is shown Complete each of the following Use interval notation when appropriate a Give the zeros of f b Give any x and y intercepts on the graph of f c Identify where f is negative or positive d Identify where f is increasing or decreasing e Is the average rate of change of f from x 4 tox 4 positive negative or zero 4 4 y f x

Exercises 65 74 Use the graph of f to determine intervals where fis increasing and where f is decreasing 65 3 K 3 1 3 1 1 23 3 3 1 23 2 3 23 123

Exercises 65 74 Use the graph of f to determine intervals where fis increasing and where f is decreasing 65 66 3 3 1 1 321 2 3 321 2 23 2 3 y 23 123 X

67 68 2 1 3 23 2 3 32 3 2 1 23 2 y 3 123 4 123 X

69 70 2 1 T T 1 2 2 2 X

Exercises 93 94 Energy The following graph shows U S Energy consumption Energy millions of Btu 400 350 300 250 200 150 100 50 1970 1990 2010 Year 93 When was energy consumption increasing 94 When was energy consumption decreasing

Exercises 39 42 Decide whether a line can pass through the data points If it can determine the slope of the like 39 40 41 X y X y X y F 4 1 5 5 2 3 1 NIH 2 3 2 2 7 0 2 1 1 3 11 2 712 3 4 4 15 4 5 5 7

Exercises 31 38 Determine if f is a linear or nonlinear function If f is a linear function determine if f is a constant function Support your answer by graphing f 31 f x 22x 5 32 f x 3x 2 33 f x 1 34 f x 2 35 f x x 1 36 f x 2x 11 37 f x x 1 38 f x x 1

Exercises 5 18 If possible find the slope of the line passing through each pair of points 5 4 6 2 5 6 8 5 3 7 7 1 4 5 2 8 10 4 15 7

A student provided the solution for solving the following equation Click on the part in which an error was made 7x X 3 48 X 3 1 7x x 3 48 1 x 3 7x 48 x 3 7 3 23 1 x 3 x 3 GO 7x 48 1 7x 49 x 7

One roofer can put a new roof on a house three times faster than another Working together they can roof a house in 5 days How many days would it take the faster roofer to put a new roof on a house working alone Round the answer to the nearest tenth Assume the roofs of the houses are similar sizes Type your numeric answer and submit 20 Hint X You are incorrect X Let X represent the number of days the faster roofer carpoof a house The other roofer will take 3x days Think about how much of the roof can be completed each day Then add these together to equal the part of the roof completed in 5

Exercises 1 4 A linear function f can be written in the form f x Identify m and b for the given f x 1 f x 5 2x 2 f x 3 4x 3 f x 8x 4 f x 6

A student provided the following solution for solving the following equation Click on the part in which an error was made 9 x 3 7 x 3 2 x 9 9 7 x 3 x 3 2 x 9 9 x 3 x 3 73 773 x 3 x 3 x 3 x 3 x 3 9 x 3 7 x 3 2 9x 27 7x 21 2 2x 6 2 2x 8 x 4 2

Simplify the product and enter the simplified result in the blank Use to denote an exponent if needed Do not insert spaces in your answer 3x x 4 x 1 3 x 4 x x You are incorrect I X

Hint wwww You are incorrect

Type your answers in all of the blanks and submit X X 2 Enter the appropriate word or expression in each blank Use to denote an exponent a The expressions a b and a b are called b The product a b a b is called the equivalent to Write your response here Write your response here Write your response here c For example x 4 x 4 Write your response here of two squares and when simplified it is Enter the simplified form of the result

2 Enter the appropriate word or phrase in each blank Use to denote an exponent Do not enter spaces in your answer Enter the simplified expressions in parts b and d a The expression a b is called the Write your response here of a binomial Please type your answer to submit b When simplified a b is equivalent to the expression d For example x 4 c This resulting trinomial is called a Write your response here Write your response here Write your response here square trinomial Open in Reading Vie

5 A trainee technician was required to carry out an analysis of a standard sample containing 31 20 alumina standard deviation 0 22 established by extensive previous analysis The trainee carried out 8 replicates with the following percentage results 31 09 28 85 31 07 31 10 31 09 31 12 I 31 07 31 13 Analyze the data at the 95 CL for gross errors calculate the mean standard deviation and relat standard deviation HINT Rejected values should not be retested nor included in the calculation of the mean SD RSD

3 2 1 3 1 1 2 3 g x 2 x URLISARIO 23 X

11 points Save Dividing people at a party into groups and then selecting two of the groups to interview is an example of which sampling method Enter the le A B C D E F in the answer blank Question 3 A Simple Random D Stratified B Systematic E Convienience C Cluster

58 9 3 3 2 1 3 g x 3 2 x 321 1 6 3 1 2 3 g x x 3

Water in a Swimming Pool The line graph represents the gallons of water W in a small swimming pool after x hours a Evaluate W 4 and interpret your result b Determine the domain D of function W and explain what it represents c Determine the range R of function W and explain what it represents y Water gallons 2000 1750 1500 1250 1000 750 500 250 y W x

Electronic Waste As technology advances there are more and more obsolete electronic devices that need to be disposed of The function f x 40x estimates the millions of tons of electronic waste that will accumulate worldwide after x years Evaluate f 5 and interpret the result Source Environmental Protection Agency

31 Height of a Golf Ball A golf ball is hit and its vertical heighth in feet above the ground after t seconds is given by h t 641 161 a What is the initial height of the golf ball b What is the height of the golf ball after 4 seconds c If the golf ball spends the same amount of time going upas coming down after how many seconds does the golf ball reach its maximum height What is the maximum height of the golf ball d Give a reasonable domain D for function h and explain what it represents e Give a reasonable range R for function and explain what it represents

Exercises 111 118 Determine if y is a function of x 111 x y 112 y x 1 113 x 1 y 114 x y 7 115 x y 70 116 x 1 y 1 117 x y 2 118 y x

5 3 2 1 3 2 3 123

1 Simplity 1 24x y4 4 A 2xy 3xy C 2y 3x 2 3 3 64v6 A C 16v i B 3y 3x D 2y 2xy B 16 D 1 276 2 2 81m A 49m m

3 13 13 14 15 4 2 3 4 2 B 14 C 2 2 6 D 5 14 6n A on c n Write each expression in radical form 6 2 5 2 2 2 2 6 2 B 3n D Write each expression in exponential form 15 3 m 44

9 V6x V2x A 2 C 12 1 11 5 20 4 4 S 5 A C 4 B 2x 3x D 2 3 B D 4 5 25 3 5 2

9 Simplify 9 6x x 2x W A 2 2 C 12 11 II 11 5 20 4 4 A C 4 B 2x 3x D 2 3 B D 4 5 25 3 5 2 10 12 10 30x 9 12 6x A 4 105x 5 3x B 27x x 6 C 54 10x 6x 30x D V105 18x 12 4 3 3 25 A C 3 12 3 2 16 ENCENSE 4 3 3 B 5 D 3 5 3 3

4 5 Write each expression in exponential form 4 7 6 A 7x C 2x Write each expression in radical form 5 5x A C SK Simplify B 7x D 3x 6 276 A 10006 C 36 B 47 DI B 95 D 2166 2924 SATILI AL ES

10 10 30x19 12 6x A 4105 5 3x B 27xx 6 C 54 10x 6x V30x D 10518c 12 443 3 25 4 3 4 3 3

m 1 3 Simplity 1 24x y A 2xy 3xy C 2y 3x 3 64 9 A C 16v 5 B D B 3y 3x D 2y 2xy 16 1 6 27 A 11 2 7 8 m 2 81m A 49m C m B 27m D m 10