Chapter 6
Algebra for College Students · 328 exercises
Problem 78
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{1}{x}+\frac{1}{x^{2}}=\frac{x+2}{x^{2}}$$
4 step solution
Problem 78
Perform the indicated operations. $$\frac{x^{3}+1}{x^{2}-1} \cdot \frac{3 x-3}{x^{3}-x^{2}+x}$$
4 step solution
Problem 78
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{3}{4}=\frac{12}{?}$$
4 step solution
Problem 79
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{1}{x}+\frac{1}{2 x}=\frac{x+2}{2 x}$$
5 step solution
Problem 79
Perform the indicated operations. $$\frac{2 h^{2}-5 h-3}{5 h^{2}-4 h-1} \div \frac{2 h^{2}+7 h+3}{h^{2}+2 h-3}$$
5 step solution
Problem 79
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{3}{a}=\frac{?}{a^{2}}$$
5 step solution
Problem 80
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{1}{x}+\frac{1}{x^{2}}=\frac{6}{x^{3}}$$
6 step solution
Problem 80
Perform the indicated operations. $$\frac{9 w^{2}-64}{3 w^{2}-5 w-8} \cdot \frac{5 w^{2}+3 w-2}{25 w^{2}-4}$$
5 step solution
Problem 80
For each pair of polynomials, use division to determine whether the first polynomial is a factor of the second. Use synthetic division when possible. If the first polynomial is a factor, then factor the second polynomial. See Example 7. $$x-1, x^{3}+3 x^{2}-5 x$$
3 step solution
Problem 80
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{5}{y}=\frac{10}{?}$$
4 step solution
Problem 81
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{1}{x}+\frac{1}{x-1}=\frac{2 x-1}{x^{2}-x}$$
6 step solution
Problem 81
Perform the indicated operations. $$\frac{9 a-3}{1-9 a^{2}} \cdot \frac{9 a^{2}+6 a+1}{6}$$
5 step solution
Problem 82
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{2}{x+1}+\frac{3}{x-1}=\frac{5 x+1}{x^{2}-1}$$
5 step solution
Problem 82
Perform the indicated operations. $$\frac{5-10 k}{k^{2}-2 k} \div \frac{2 k^{2}+7 k-4}{k^{2}+2 k-8}$$
5 step solution
Problem 82
For each pair of polynomials, use division to determine whether the first polynomial is a factor of the second. Use synthetic division when possible. If the first polynomial is a factor, then factor the second polynomial. See Example 7. $$x+8, x^{2}+3 x-40$$
4 step solution
Problem 82
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{3}{x-4}=\frac{?}{4-x}$$
4 step solution
Problem 83
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{1}{x}+\frac{1}{x-1}=\frac{2 x}{x^{2}-x}$$
5 step solution
Problem 83
Perform the indicated operations. $$\frac{k^{2}+2 k m+m^{2}}{k^{2}-2 k m+m^{2}} \cdot \frac{m^{2}+3 m-m k-3 k}{m^{2}+m k+3 m+3 k}$$
6 step solution
Problem 83
For each pair of polynomials, use division to determine whether the first polynomial is a factor of the second. Use synthetic division when possible. If the first polynomial is a factor, then factor the second polynomial. See Example 7. $$w-3, w^{3}-27$$
3 step solution
Problem 84
Solve each equation. Identify each equation as a conditional equation, an inconsistent equation, or an identity. State the solution sets to the identities using interval notation. $$\frac{2}{x+1}+\frac{3}{x-1}=\frac{5 x+2}{x^{2}-1}$$
7 step solution
Problem 84
Perform the indicated operations. $$\frac{a^{2}+2 a b+b^{2}}{a c+b c-a d-b d} \div \frac{a c+a d-b c-b d}{c^{2}-d^{2}}$$
4 step solution
Problem 84
For each pair of polynomials, use division to determine whether the first polynomial is a factor of the second. Use synthetic division when possible. If the first polynomial is a factor, then factor the second polynomial. See Example 7. $$w+5, w^{3}+125$$
4 step solution
Problem 85
Solve each problem. Aspect ratio. The aspect ratio for a television screen is the ratio of the width to the height of the screen. For a high definition TV it is 16 to \(9 .\) What is the height of a screen that is 48 inches wide?
5 step solution
Problem 85
Perform the indicated operations. Variables in exponents represent integers. $$\frac{x^{a}}{y^{2}} \cdot \frac{y^{b+2}}{x^{2 a}}$$
6 step solution
Problem 85
Perform the indicated operations. $$ \frac{w^{2}-3 w+6}{w-5}+\frac{9-w^{2}}{w-5} $$
3 step solution
Problem 85
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{2}{w-3}=\frac{-2}{?}$$
4 step solution
Problem 86
Solve each problem. Hybrids. The ratio of the number of cars with gasoline engines to hybrids sold at a car dealer is 9 to \(2 .\) If the dealer sells 10 hybrids one month, then how many gasoline cars did the dealer sell?
5 step solution
Problem 86
Perform the indicated operations. Variables in exponents represent integers. $$\frac{x^{3 a+1}}{y^{2 b-3}} \cdot \frac{y^{3 b+4}}{x^{2 a-1}}$$
3 step solution
Problem 86
$$ \frac{w^{2}-3 w+6}{w-5}+\frac{9-w^{2}}{w-5} $$$$ \frac{2 z^{2}-3 z+6}{z^{2}-1}-\frac{z^{2}-5 z+9}{z^{2}-1} $$
6 step solution
Problem 87
Solve each problem. Maritime losses. The amount paid to an insured party by the American Insurance Company is computed by using the proportion \(\frac{\text { value shipped }}{\text { amount of loss }}=\frac{\text { amount of declared premium }}{\text { amount insured party gets paid }}\) If the value shipped was \(\$ 300,000,\) the amount of loss was \(\$ 250,000,\) and the amount of declared premium was \(\$ 200,000,\) then what amount is paid to the insured party?
4 step solution
Problem 87
Perform the indicated operations. Variables in exponents represent integers. $$\frac{x^{2 a}+x^{a}-6}{x^{2 a}+6 x^{a}+9} \div \frac{x^{2 a}-4}{x^{2 a}+2 x^{a}-3}$$
5 step solution
Problem 87
Perform the indicated operations. $$ \frac{2 z^{2}-3 z+6}{z^{2}-1}-\frac{z^{2}-5 z+9}{z^{2}-1} $$
7 step solution
Problem 87
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{2 x+4}{6}=\frac{?}{3}$$
3 step solution
Problem 88
Perform the indicated operations. Variables in exponents represent integers. $$\frac{w^{2 b}+2 w^{b}-8}{w^{2 b}+3 w^{b}-4} \div \frac{w^{2 b}-w^{b}-2}{w^{2 b}-1}$$
3 step solution
Problem 88
Perform the indicated operations. $$ \frac{3}{6 x^{2}-4 x}-\frac{x-2}{9 x-6} $$
4 step solution
Problem 88
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{2 x-3}{4 x-6}=\frac{1}{?}$$
5 step solution
Problem 89
Solve each problem. Capture-recapture method. To estimate the size of the grizzly bear population in a national park, rangers tagged and released 12 bears. Later it was observed that in 23 sightings of grizzly bears, only two had been tagged. Assuming the proportion of tagged bears in the later sightings is the same as the proportion of tagged bears in the population, estimate the number of bears in the population.
5 step solution
Problem 89
Perform the indicated operations. Variables in exponents represent integers. $$\frac{m^{k} v^{k}+3 v^{k}-2 m^{k}-6}{m^{2 k}-9} \cdot \frac{m^{2 k}-2 m^{k}-3}{v^{k} m^{k}-2 m^{k}+2 v^{k}-4}$$
3 step solution
Problem 89
Perform the indicated operations. $$ \frac{x-1}{2 x^{2}+3 x+1}-\frac{x+1}{2 x^{2}-x-1} $$
7 step solution
Problem 89
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{3 a+3}{3 a}=\frac{?}{a}$$
4 step solution
Problem 90
Solve each problem. Please rewind. In a sample of 24 returned videotapes, it was found that only 3 were rewound as requested. If 872 videos are returned in a day, then how many of them would you expect to find that are not rewound?
3 step solution
Problem 90
Perform the indicated operations. Variables in exponents represent integers. $$\frac{m^{3 k}-1}{m^{3 k}+1} \cdot \frac{m^{2 k+1}-m^{k+1}+m}{m^{3 k}+m^{2 k}+m^{k}}$$
5 step solution
Problem 90
Perform the indicated operations. $$ \frac{2 x+1}{6 x^{2}-5 x+1}+\frac{2 x-1}{6 x^{2}+x-1} $$
7 step solution
Problem 90
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{x-3}{x^{2}-9}=\frac{1}{?}$$
4 step solution
Problem 91
Solve each problem. Pleasing painting. The ancient Greeks often used the ratio of length to width for a rectangle as 7 to 6 to give the rectangle a pleasing shape. If the length of a pleasantly shaped Greek painting is 22 centimeters (cm) longer than its width, then what are its length and width?
5 step solution
Problem 91
Perform the indicated operations. $$ \frac{\left(a^{2} b^{3}\right)^{4}}{\left(a b^{4}\right)^{3}} \cdot \frac{(a b)^{3}}{\left(a^{4} b\right)^{2}} $$
5 step solution
Problem 91
Perform the indicated operations. $$ \frac{2 x+1}{6 x^{2}-5 x+1}+\frac{2 x-1}{6 x^{2}+x-1} $$
8 step solution
Problem 91
In place of each question mark in Exercises \(75-92,\) put an expression that will make the rational expressions equivalent. $$\frac{1}{x-1}=\frac{?}{x^{3}-1}$$
4 step solution
Problem 92
Solve each problem. Pickups and cars. The ratio of pickups to cars sold at a dealership is 2 to \(3 .\) If the dealership sold 142 more cars than pickups in \(2006,\) then how many of each did it sell?
7 step solution
Problem 92
Perform the indicated operations. $$ \frac{(a b)^{2}}{(a+b)^{2}} \cdot \frac{(a+b)^{3}}{(a b)^{3}} $$
5 step solution