# Questions on Algebra: Polynomials, rational expressions and equations answered by real tutors!

Algebra ->  Algebra  -> Polynomials-and-rational-expressions -> Questions on Algebra: Polynomials, rational expressions and equations answered by real tutors!      Log On

 Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations! Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

 Algebra: Polynomials, rational expressions and equations Solvers Lessons Answers archive Quiz In Depth

 Question 262918: Evaluate each rational expression Evaluate 3x+1/4x-4 for x = 5 Click here to see answer by Nieleya(22)

 Question 262915: Find an nth degree polynominal function with the real coefficient satisfying the given conditions. n=3;-2 and -2+3i are zero;leading coefficient is 1 Click here to see answer by ankor@dixie-net.com(15747)

 Question 263110: P dollars is invested at annual interest rate r for 1 year. If the interest is compounded semiannually, then the polynomial P(1+r/2)^2 represents the value of the investment after 1 year. Rewrite this expression without parentheses. Evaluate the polynomial if P = \$200 and r = 10%. Click here to see answer by drk(1908)

 Question 263141: The equation D=1.2 sqrt h gives the distance, D in miles that a person can see to the horizon from a height, h, in feet. A technician can see 30.4 miles to the horizon from the top of a radio tower. How high is the tower? (Replace the known values in the equation D=1.2 sqrt h) Click here to see answer by drk(1908)

 Question 263137: After an accident, polie determine the spped at which the car had been traveling based on the length of the skid marks the car left on the road. The police use the following formula: r= 2(over)/(5L)^-1/2, where r is the speed of the car, in miles per housr, and L is the distance of the skid marks, in feet. A. Solve the equation r= 2(over)/(5L)^-1/2 for L. (Apply rule of negative and fractional exponents before solving for the variable L.) B. How far will a car skid at 65 mph? Round your answer to the nearest whole, feet if necessary. (Use your equation in 1A and replace the known values in the equation. Thanks!!! Click here to see answer by stanbon(57984)

 Question 263246: How do I start to solve this problem? I have tried to solve but I am so confused. ACTIVITY 1: ISBNS AND THE CHECK DIGIT (20 points) Each activity in this text is designed to either enhance your understanding of the topics of the preceding chapter, provide you with a mathematical extension of those topics, or both. The activities can be undertaken by one student, but they are better suited for a small group project. Occasionally it is only through discussion that different facets of the activity become apparent. For material related to this activity, visit the text website at www.mhhe.com/streeter. Have you ever noticed the long number, usually accompanied by a bar code, that can be found on the back of a book? This is called the International Standard Book Number (ISBN). Each book has a unique ISBN, which is 10 digits in length. The most common form for an ISBN is X-XX-XXXXXX-X. Each ISBN has four blocks of digits. • The first block of digits on the left represents the language of the book (0 is used to represent English). This block is usually one digit in length. • The second block of digits represents the publisher. This block is usually two or three digits in length. • The third block of digits represents the number assigned to the book by the publishing company. This is usually five or six digits in length. • The fourth block consists of the check digit. For the purposes of this document, we will consider the ISBN 0-07-229654-2. The digit of most interest is the final digit, the check digit. When an ISBN is entered into a computer, the computer looks at the check digit to make certain that the numbers were properly entered. We will look at the algorithm used to generate the check digit. Activity I. To determine the check digit for the ISBN of a text, follow these steps. 1. Multiply each of the nine assigned digits by a weighted value. The weighted values are 1 for the first digit from the left, 2 for the second digit, 3 for third digit, etc. In our case, we have 1 • 0 + 2 • 0 + 3 • 7 + 4 • 2 + 5 • 2 + 6 • 9 + 7 • 6 + 8 • 5 + 9 • 4 = 211 2. In mathematics, we occasionally are interested in only the remainder after we do division. We refer to the remainder as the modular (or mod) of the divisor. The ISBN uses (mod 11) to determine the check digit. 211 ÷ 11 = 19 with a remainder of 2. We say 211 = 2 (mod 11) That is how we get the 2 in the ISBN 0-07-229654-2. II. If we are given an ISBN and we want to check its validity, we can follow a similar algorithm. 1. Multiply each of the 10 digits by a weighted value. The weighted values are still 1 for the first digit from the left, 2 for the second digit, etc., but we also multiply 10 times the tenth (check) digit. In our case, we now have 1 • 0 + 2 • 0 + 3 • 7 + 4 • 2 + 5 • 2 + 6 • 9 + 7 • 6 + 8 • 5 + 9 • 4 + 10 • 2 = 231 2. For any valid ISBN, the result will have a remainder of zero when divided by 11. In other words, we will have 0 (mod 11). Note that 231 ÷ 11 = 21. Determine whether each of the following is a valid ISBN. 0-07-038023-6 0-15-249584-2 0-553-34948-1 0-07-000317-3 For those numbers above that are valid, go on-line and find the books to which they refer. Click here to see answer by mducky2(62)

 Question 263313: Find the LCD for the given rational expressions, and convert each rational expression into an equivalent rational expression with the LCD as the denominator. 4/(x-y),5x/(2y-2x) Click here to see answer by stanbon(57984)

 Question 263217: Worker efficiency. In a study of worker efficiency at Wong Laboratories it was found that the number of components assembled per hour by the average worker t hours after starting work could be modeled by the formula N(t)=-3t^3 + 23t^2 +8t. a) Rewrite the formula by factoring the right-hand side completely. b) Use the factored version of the formula to find N(3). c) Use the accompanying graph to estimate the time at which the workers are most efficient. d) Use the accompanying graph to estimate the maximum number of components assembled per hour during an 8-hour shift. Click here to see answer by ankor@dixie-net.com(15747)

 Question 263411: Factor the expression on the left side of each equation. Then solve the equation 4x³-32=0 Click here to see answer by drk(1908)

 Question 263473: Multiply and simplify by factoring. Assume that all expressions under radicals represent non negative numbers. (^3sqrt r^13)(^3sqrt16y^14) Click here to see answer by checkley77(12569)

 Question 263682: find all numbers for which the rational expression is undefined (9)/(5v+4) Click here to see answer by stanbon(57984)

 Question 263696: Find a polynomial with integer coefficients and a leading coefficient of one that satisfies the given conditions. P has degree 3, and zeros 1 and 4 + 4i. Click here to see answer by palanisamy(496)

 Question 264014: I don't understand this question: factor the polynomial; 25x to the second -169t to the second thanks. Click here to see answer by stanbon(57984)

 Question 264019: can you help me with this question: factor the trimonial a to the second+2a-63 thanks Click here to see answer by jim_thompson5910(28717)

 Question 264016: Need help with finding the factor for the perfect square trinomial 64b to the second-112b+49 thanks Click here to see answer by jim_thompson5910(28717)

 Question 264021: I need help finding the factor for the trinomial and factor out all common monomials first. If the trinomial is prime then put prime: -y to the second -2y+35 thank you Click here to see answer by stanbon(57984)

 Question 264047: This is the question: A small box is placed inside a larger box. The dimensions of the small box are x+1 by x+2 by x-1. The dimensions of the larger box are 2x by x+4 by x+2. a)Write an equation for the volume of the space inside the larger box but outside the smaller box. I solved this and got x^3+10x^2+17x+2. b)If the volume of the space inside the larger box but outside the smaller box is equal to 33x+162 cubic units, what is x? I also solved this and got x=4. c)What is the volume of the smaller box? d)What is the volume of the larger box? I need help with c) and d) please. Thank you Click here to see answer by jim_thompson5910(28717)

 Question 264013: I need help with this expression: factor the expression: m to the third-27n to the third thanks Click here to see answer by drk(1908)

 Question 264081: I need to solve this problem in synthetic division. (x2-3x+2)/(x-1) Click here to see answer by Greenfinch(383)

 Question 264119: Help please! State any restrictions on x. And solve for x. 5 over (3x) + 2 over (x^2) equals 7 over (9) denminators in () Click here to see answer by stanbon(57984)

 Question 264117: Help please! State any restrictions on x. And solve for x. 5 2 7 - + - = - 3x x^2 9 Click here to see answer by ankor@dixie-net.com(15747)

 Question 264010: I need help factoring polynomial of this question: bc+b+cd+d thank you! Click here to see answer by ankor@dixie-net.com(15747)