Chapter 11
Prealgebra and Introductory Algebra · 393 exercises
Problem 31
For Exercises 21 to \(32,\) solve for \(y\). $$x+3 y=6$$
3 step solution
Problem 31
Simplify. $$\frac{x^{2}+3 x-28}{24-2 x-x^{2}}$$
2 step solution
Problem 31
Simplify. $$\frac{x-\frac{2}{2 x-3}}{2 x-1-\frac{8}{2 x-3}}$$
4 step solution
Problem 32
Two machines fill cereal boxes at the same rate. After the two machines work together for \(7 \mathrm{h}\), one machine breaks down. The second machine requires 14 more hours to finish filling the boxes. How long would it have taken one of the machines, working alone, to fill the boxes?
3 step solution
Problem 32
Simplify. $$\frac{7}{4 y}+\frac{11}{6 y}-\frac{8}{3 y}$$
3 step solution
Problem 32
Solve. $$2+\frac{3}{a-3}=\frac{a}{a-3}$$
4 step solution
Problem 32
Write the fractions in terms of the LCM of the denominators. $$\frac{5 y}{6 x^{2}}, \frac{7}{9 x y}$$
3 step solution
Problem 32
For Exercises 21 to \(32,\) solve for \(y\). $$x+2 y=8$$
2 step solution
Problem 32
Simplify. $$\frac{x^{2}+7 x-8}{1+x-2 x^{2}}$$
3 step solution
Problem 32
Simplify. $$\frac{x+3-\frac{18}{2 x+1}}{x-\frac{6}{2 x+1}}$$
4 step solution
Problem 33
A mechanic requires \(2 \mathrm{h}\) to repair a transmission, whereas an apprentice requires \(6 \mathrm{h}\) to make the same repairs. The mechanic worked alone for \(1 \mathrm{h}\) and then stopped. How long will it take the apprentice, working alone, to complete the repairs?
4 step solution
Problem 33
Simplify. $$\frac{5}{3 x}-\frac{2}{x^{2}}+\frac{3}{2 x}$$
4 step solution
Problem 33
Solve. $$\frac{x}{x+4}=3-\frac{4}{x+4}$$
3 step solution
Problem 33
Write the fractions in terms of the LCM of the denominators. $$\frac{y}{x(x-3)}, \frac{6}{x^{2}}$$
3 step solution
Problem 33
Multiply. $$\frac{8 x^{2}}{9 y^{3}} \cdot \frac{3 y^{2}}{4 x^{3}}$$
4 step solution
Problem 33
Simplify. $$\frac{\frac{1}{x}-\frac{2}{x-1}}{\frac{3}{x}+\frac{1}{x-1}}$$
3 step solution
Problem 34
A large drain and a small drain are opened to drain a pool. The large drain can empty the pool in 6 h. After both drains have been open for 1 h, the large drain becomes clogged and is closed. The small drain remains open and requires 9 more hours to empty the pool. How long would it have taken the small drain, working alone, to empty the pool?
3 step solution
Problem 34
Simplify. $$\frac{6}{y^{2}}+\frac{3}{4 y}-\frac{2}{5 y}$$
3 step solution
Problem 34
Solve. $$\frac{x}{x-1}=\frac{8}{x+2}$$
4 step solution
Problem 34
Write the fractions in terms of the LCM of the denominators. $$\frac{a}{y^{2}}, \frac{6}{y(y+5)}$$
3 step solution
Problem 34
Multiply. $$\frac{14 a^{2} b^{3}}{15 x^{5} y^{2}} \cdot \frac{25 x^{3} y}{16 a b}$$
3 step solution
Problem 34
Simplify. $$\frac{\frac{3}{n+1}+\frac{1}{n}}{\frac{2}{n+1}+\frac{3}{n}}$$
3 step solution
Problem 35
It takes Sam \(h\) hours to rake the yard, and it takes Emma \(k\) hours to rake the yard, where \(h>k .\) Let \(t\) be the amount of time it takes Sam and Emma to rake the yard together. Is \(t\) less than \(k\), between \(k\) and \(h\), or greater than \(k\) ?
4 step solution
Problem 35
Simplify. $$\frac{2}{x}-\frac{3}{2 y}+\frac{3}{5 x}-\frac{1}{4 y}$$
4 step solution
Problem 35
Solve. $$\frac{x}{x+12}=\frac{1}{x+5}$$
4 step solution
Problem 35
Write the fractions in terms of the LCM of the denominators. $$\frac{9}{(x-1)^{2}}, \frac{6}{x(x-1)}$$
3 step solution
Problem 35
Multiply. $$\frac{12 x^{3} y^{4}}{7 a^{2} b^{3}} \cdot \frac{14 a^{3} b^{4}}{9 x^{2} y^{2}}$$
4 step solution
Problem 35
Simplify. $$\frac{\frac{3}{2 x-1}-\frac{1}{x}}{\frac{4}{x}+\frac{2}{2 x-1}}$$
4 step solution
Problem 36
Simplify. $$\frac{5}{2 a}+\frac{7}{3 b}-\frac{2}{b}-\frac{3}{4 a}$$
5 step solution
Problem 36
Solve. $$\frac{2 x}{x+4}=\frac{3}{x-1}$$
5 step solution
Problem 36
Write the fractions in terms of the LCM of the denominators. $$\frac{a^{2}}{y(y+7)}, \frac{a}{(y+7)^{2}}$$
3 step solution
Problem 36
Multiply. $$\frac{18 a^{4} b^{2}}{25 x^{2} y^{3}} \cdot \frac{50 x^{5} y^{6}}{27 a^{6} b^{2}}$$
3 step solution
Problem 36
Simplify. $$\frac{\frac{4}{3 x+1}+\frac{3}{x}}{\frac{6}{x}-\frac{2}{3 x+1}}$$
4 step solution
Problem 37
Simplify. $$\frac{2 x+1}{3 x}+\frac{x-1}{5 x}$$
4 step solution
Problem 37
Solve. $$\frac{5}{3 n-8}=\frac{n}{n+2}$$
5 step solution
Problem 37
Write the fractions in terms of the LCM of the denominators. $$\frac{3}{x-3}, \frac{5}{x(3-x)}$$
3 step solution
Problem 37
Multiply. $$\frac{3 x-6}{5 x-20} \cdot \frac{10 x-40}{27 x-54}$$
4 step solution
Problem 37
True or false? If the denominator of a complex fraction is the reciprocal of the numerator, then the complex fraction is equal to the square of its numerator.
3 step solution
Problem 38
Simplify. $$\frac{4 x-3}{6 x}+\frac{2 x+3}{4 x}$$
5 step solution
Problem 38
Solve. $$\frac{x}{x+4}=\frac{11}{x^{2}-16}+2$$
3 step solution
Problem 38
Write the fractions in terms of the LCM of the denominators. $$\frac{b}{y(y-4)}, \frac{b^{2}}{4-y}$$
3 step solution
Problem 38
Multiply. $$\frac{8 x-12}{14 x+7} \cdot \frac{42 x+21}{32 x-48}$$
3 step solution
Problem 38
Simplify. $$1+\frac{1}{1+\frac{1}{2}}$$
4 step solution
Problem 39
A camper drove 80 mi to a recreational area and then hiked 4 mi into the woods. The rate of the camper while driving was ten times the rate while hiking. The total time spent hiking and driving was 3 h. Find the rate at which the camper hiked.
3 step solution
Problem 39
Simplify. $$\frac{x-3}{6 x}+\frac{x+4}{8 x}$$
6 step solution
Problem 39
Solve. $$x-\frac{6}{x-3}=\frac{2 x}{x-3}$$
5 step solution
Problem 39
Write the fractions in terms of the LCM of the denominators. $$\frac{x-2}{x+3}, \frac{x}{x-4}$$
4 step solution
Problem 39
Multiply. $$\frac{3 x^{2}+2 x}{2 x y-3 y} \cdot \frac{2 x y^{3}-3 y^{3}}{3 x^{3}+2 x^{2}}$$
3 step solution
Problem 39
Simplify. $$1+\frac{1}{1+\frac{1}{1+\frac{1}{2}}}$$
4 step solution
Problem 40
The president of a company traveled 1800 mi by jet and 300 \(\mathrm{mi}\) on a prop plane. The rate of the jet was four times the rate of the prop plane. The entire trip took 5 h. Find the rate of the jet.
3 step solution