Chapter 11
Prealgebra and Introductory Algebra · 393 exercises
Problem 9
Simplify. $$\frac{2-\frac{8}{x+4}}{3-\frac{12}{x+4}}$$
3 step solution
Problem 10
If a plane flies 300 mph in calm air and the rate of the wind is \(r\) miles per hour, then the rate of the plane flying with the wind can be represented as ______, and the rate of the plane flying against the wind can be represented as _______.
3 step solution
Problem 10
Simplify. $$\frac{6 y}{4 y+1}-\frac{11 y}{4 y+1}$$
4 step solution
Problem 10
Solve. $$\frac{x}{3}-\frac{1}{4}=\frac{x}{4}-\frac{1}{6}$$
3 step solution
Problem 10
Solve the formula for the given variable. $$F=\frac{9}{5} C+32 ; C \quad \text { (Temperature conversion) }$$
4 step solution
Problem 10
Simplify. $$\frac{5-2 x}{2 x-5}$$
3 step solution
Problem 10
Find the LCM of the polynomials. $$\begin{aligned} &8 x^{2}(x-1)^{2}\\\ &10 x^{3}(x-1) \end{aligned}$$
3 step solution
Problem 10
Simplify. $$\frac{5-\frac{25}{x+5}}{1-\frac{3}{x+5}}$$
3 step solution
Problem 11
Suppose you have a powerboat with the throttle set to move the boat at 8 mph in calm water, and the rate of the current is \(4 \mathrm{mph}\). a. What is the speed of the boat when traveling with the current? \(\mathbf{b}\). What is the speed of the boat when traveling against the current?
2 step solution
Problem 11
Simplify. $$\frac{2 x+1}{x-3}+\frac{3 x+6}{x-3}$$
3 step solution
Problem 11
Solve. $$\frac{2 y}{9}-\frac{1}{6}=\frac{y}{9}+\frac{1}{6}$$
3 step solution
Problem 11
Solve the formula for the given variable. $$A=\frac{1}{2} h\left(b_{1}+b_{2}\right) ; b_{1} \quad \text { (Geometry) }$$
4 step solution
Problem 11
Find the LCM of the polynomials. $$\begin{aligned} &3 x+3\\\ &2 x^{2}+4 x+2 \end{aligned}$$
3 step solution
Problem 11
Simplify. $$\frac{6 y(y+2)}{9 y^{2}(y+2)}$$
3 step solution
Problem 11
Simplify. $$\frac{1+\frac{5}{y-2}}{1-\frac{2}{y-2}}$$
4 step solution
Problem 12
The speed of a plane is 500 mph. There is a headwind of 50 mph. What is the speed of the plane relative to an observer on the ground?
3 step solution
Problem 12
Simplify. $$\frac{4 x+3}{2 x-7}+\frac{3 x-8}{2 x-7}$$
3 step solution
Problem 12
Solve. $$\frac{2 x-5}{8}+\frac{1}{4}=\frac{x}{8}+\frac{3}{4}$$
3 step solution
Problem 12
Solve the formula for the given variable. $$s=a(x-v t) ; t \quad \text { (Physics) }$$
2 step solution
Problem 12
Find the LCM of the polynomials. $$\begin{aligned} &4 x-12\\\ &2 x^{2}-12 x+18 \end{aligned}$$
3 step solution
Problem 12
Simplify. $$\frac{12 x^{2}(3-x)}{18 x(3-x)}$$
3 step solution
Problem 12
Simplify. $$\frac{2-\frac{11}{2 x-1}}{3-\frac{17}{2 x-1}}$$
3 step solution
Problem 13
Simplify. $$\frac{5 x-1}{x+9}-\frac{3 x+4}{x+9}$$
4 step solution
Problem 13
Solve the formula for the given variable. $$V=\frac{1}{3} A h ; h \quad \text { (Geometry) }$$
3 step solution
Problem 13
Solve. $$\frac{3 x+4}{12}-\frac{1}{3}=\frac{5 x+2}{12}-\frac{1}{2}$$
4 step solution
Problem 13
Find the LCM of the polynomials. $$\begin{aligned} &(x-1)(x+2)\\\ &(x-1)(x+3) \end{aligned}$$
3 step solution
Problem 13
Simplify. $$\frac{6 x(x-5)}{8 x^{2}(5-x)}$$
4 step solution
Problem 13
Simplify. $$\frac{4-\frac{2}{x+7}}{5+\frac{1}{x+7}}$$
2 step solution
Problem 14
Simplify. $$\frac{6 x-5}{x-10}-\frac{3 x-4}{x-10}$$
5 step solution
Problem 14
Solve. $$\frac{6}{2 a+1}=2$$
4 step solution
Problem 14
Solve the formula for the given variable. $$P=R-C ; C \quad \text { (Business) }$$
2 step solution
Problem 14
Find the LCM of the polynomials. $$\begin{aligned} &(2 x-1)(x+4)\\\ &(2 x+1)(x+4) \end{aligned}$$
3 step solution
Problem 14
Simplify. $$\frac{14 x^{3}(7-3 x)}{21 x(3 x-7)}$$
5 step solution
Problem 14
Simplify. $$\frac{5+\frac{3}{x-8}}{2-\frac{1}{x-8}}$$
4 step solution
Problem 15
A park has two sprinklers that are used to fill a fountain. One sprinkler can fill the fountain in \(3 \mathrm{h}\), whereas the second sprinkler can fill the fountain in \(6 \mathrm{h}\). How long will it take to fill the fountain with both sprinklers operating?
3 step solution
Problem 15
Simplify. $$\frac{x-7}{2 x+7}-\frac{4 x-3}{2 x+7}$$
3 step solution
Problem 15
Solve. $$\frac{12}{3 x-2}=3$$
3 step solution
Problem 15
Solve the formula for the given variable. $$R=\frac{C-S}{t} ; S \quad \text { (Business) }$$
3 step solution
Problem 15
Simplify. $$\frac{1-\frac{1}{x}-\frac{6}{x^{2}}}{1-\frac{9}{x^{2}}}$$
4 step solution
Problem 15
Find the LCM of the polynomials. $$\begin{array}{l} (2 x+3)^{2} \\ (2 x+3)(x-5) \end{array}$$
3 step solution
Problem 15
Simplify. $$\frac{a^{2}+4 a}{a b+4 b}$$
3 step solution
Problem 16
One grocery clerk can stock a shelf in 20 min. A second clerk requires 30 min to stock the same shelf. How long would it take to stock the shelf if the two clerks worked together?
3 step solution
Problem 16
Simplify. $$\frac{2 n}{3 n+4}-\frac{5 n-3}{3 n+4}$$
3 step solution
Problem 16
Solve. $$\frac{9}{2 x-5}=-2$$
3 step solution
Problem 16
Solve the formula for the given variable. $$P=\frac{R-C}{n} ; R \quad \text { (Business) }$$
2 step solution
Problem 16
Simplify. $$\frac{1+\frac{4}{x}+\frac{4}{x^{2}}}{1-\frac{2}{x}-\frac{8}{x^{2}}}$$
3 step solution
Problem 16
Find the LCM of the polynomials. $$\begin{aligned} &(x-7)(x+2)\\\ &(x-7)^{2} \end{aligned}$$
3 step solution
Problem 16
Simplify. $$\frac{x^{2}-3 x}{2 x-6}$$
3 step solution
Problem 17
It takes Doug 6 days to reroof a house. If Doug's son helps him, the job can be completed in 4 days. How long would it take Doug's son, working alone, to do the job?
4 step solution
Problem 17
One person with a skiploader requires 12 h to transfer a large quantity of earth. With a larger skiploader, the same amount of earth can be transferred in \(4 \mathrm{h}\). How long would it take to transfer the earth if both skiploaders were operated together?
3 step solution