Chapter 2
Algebra and Trigonometry Real Mathematics, Real People · 560 exercises
Problem 60
Solving an Equation Involving an Absolute Value Find all solutions of the equation algebraically. Check your solutions. $$|3 x+2|=7$$
4 step solution
Problem 60
Determine the intervals on which the polynomial is entirely negative and those on which it is entirely positive. $$-2 x^{2}+x+5$$
3 step solution
Problem 60
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$x^{2}+16=-5 x$$
4 step solution
Problem 60
Use a graphing utility to approximate any solutions of the equation. [Remember to write the equation in the form \(f(x)=0.1\) $$8-\sqrt{x+9}=6$$
4 step solution
Problem 60
Write the quotient in standard form. $$\frac{8-7 i}{1-2 i}$$
6 step solution
Problem 61
Solving an Equation Involving an Absolute Value Find all solutions of the equation algebraically. Check your solutions. $$|x|=x^{2}+x-24$$
4 step solution
Problem 61
Determine the intervals on which the polynomial is entirely negative and those on which it is entirely positive. $$-x^{2}+6 x-10$$
3 step solution
Problem 61
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$4 x=8-x^{2}$$
4 step solution
Problem 61
(a) Use a graphing utility to complete the table. Determine the interval in which the solution to the equation \(3.2 x-5.8=0\) is located. Explain your reasoning. $$\begin{array}{|l|l|l|l|l|l|l|} \hline x & -1 & 0 & 1 & 2 & 3 & 4 \\ \hline 3.2 x-5.8 & & & & & & \\ \hline \end{array}$$ (b) Use the graphing utility to complete the table. Determine the interval in which the solution to the equation \(3.2 x-5.8=0\) is located. Explain how this process can be used to approximate the solution to any desired degree of accuracy. Then use the graphing utility to verify graphically the solution to \(3.2 x-5.8=0\) $$\begin{array}{|l|l|l|l|l|l|l|} \hline x & 1.5 & 1.6 & 1.7 & 1.8 & 1.9 & 2 \\ \hline 3.2 x-5.8 & & & & & & \\ \hline \end{array}$$
5 step solution
Problem 61
A certificate of deposit with an initial deposit of \(\$ 8000\) accumulates \(\$ 200\) interest in 2 years. Find the annual simple interest rate.
4 step solution
Problem 61
Write the quotient in standard form. $$\frac{i}{(4-5 i)^{2}}$$
4 step solution
Problem 62
Solving an Equation Involving an Absolute Value Find all solutions of the equation algebraically. Check your solutions. $$\left|x^{2}+6 x\right|=3 x+18$$
5 step solution
Problem 62
Determine the intervals on which the polynomial is entirely negative and those on which it is entirely positive. $$3 x^{2}+8 x+6$$
4 step solution
Problem 62
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$8 x=4-x^{2}$$
3 step solution
Problem 62
You plan to invest \(\$ 12,000\) in two funds paying \(4 \frac{1}{2} \%\) and \(5 \%\) simple interest. (There is more risk in the \(5 \%\) fund.) Your goal is to obtain a total annual interest income of \(\$ 560\) from the investments. What is the least amount you can invest in the \(5 \%\) fund to meet your objective?
5 step solution
Problem 62
Write the quotient in standard form. $$\frac{5 i}{(2+3 i)^{2}}$$
4 step solution
Problem 63
Solving an Equation Involving an Absolute Value Find all solutions of the equation algebraically. Check your solutions. $$|x+1|=x^{2}-5$$
4 step solution
Problem 63
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$x^{2}+4 x+4 \geq 9$$
5 step solution
Problem 63
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$20 x^{2}-20 x+5=0$$
5 step solution
Problem 63
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &y=6-x\\\ &y=3 x-2 \end{aligned}$$
4 step solution
Problem 63
A grocer mixes peanuts that cost \(\$ 2.50\) per pound and walnuts that cost \(\$ 8.00\) per pound to make 100 pounds of a mixture that costs \(\$ 5.25\) per pound. How much of each kind of nut is put into the mixture?
3 step solution
Problem 63
Perform the operation and write the result in standard form. $$\frac{2}{1+i}-\frac{3}{1-i}$$
3 step solution
Problem 64
Solving an Equation Involving an Absolute Value Find all solutions of the equation algebraically. Check your solutions. $$|x-15|=x^{2}-15 x$$
4 step solution
Problem 64
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$x^{2}-6 x+9<16$$
6 step solution
Problem 64
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$9 x^{2}-18 x+9=0$$
4 step solution
Problem 64
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &y=2 x-3\\\ &y=9-x \end{aligned}$$
4 step solution
Problem 64
A forester mixes gasoline and oil to make 2 gallons of mixture for a two-cycle chainsaw engine. This mixture is 32 parts gasoline and 1 part oil. How much gasoline must be added to bring the mixture to 40 parts gasoline and 1 part oil?
3 step solution
Problem 64
Perform the operation and write the result in standard form. $$\frac{2 i}{2+i}+\frac{5}{2-i}$$
4 step solution
Problem 65
Graphical Analysis (a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, (c) set \(y=0\) and solve the resulting equation, and (d) compare the result of part (c) with the \(x\) -intercepts of the graph. $$y=x^{3}-2 x^{2}-3 x$$
4 step solution
Problem 65
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$(x+2)^{2}<25$$
4 step solution
Problem 65
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$16 x^{2}+24 x+9=0$$
5 step solution
Problem 65
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &2 x+y=6\\\ &-x+y=0 \end{aligned}$$
3 step solution
Problem 65
A store has \(\$ 40,000\) of inventory in notebook computers and tablet computers. The profit on a notebook computer is \(20 \%\) and the profit on a tablet computer is \(25 \%\). The profit for the entire stock is \(24 \% .\) How much is invested in notebook computers and how much in tablet computers?
4 step solution
Problem 65
Perform the operation and write the result in standard form. $$\frac{i}{3-2 i}+\frac{2 i}{3+8 i}$$
4 step solution
Problem 66
Graphical Analysis (a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, (c) set \(y=0\) and solve the resulting equation, and (d) compare the result of part (c) with the \(x\) -intercepts of the graph. $$y=2 x^{4}-15 x^{3}+18 x^{2}$$
4 step solution
Problem 66
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$(x-3)^{2} \geq 1$$
3 step solution
Problem 66
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$9 x^{2}+30 x+25=0$$
3 step solution
Problem 66
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &x-y=-4\\\ &x+2 y=5 \end{aligned}$$
4 step solution
Problem 66
A store has \(\$ 4500\) of inventory in \(8 \times 10\) picture frames and \(5 \times 7\) picture frames. The profit on an \(8 \times 10\) frame is \(25 \%\) and the profit on a \(5 \times 7\) frame is \(22 \%\). The profit on the entire stock is \(24 \% .\) How much is invested in the \(8 \times 10\) picture frames and how much in the \(5 \times 7\) picture frames?
4 step solution
Problem 66
Perform the operation and write the result in standard form. $$\frac{1+i}{i}-\frac{3}{4-i}$$
3 step solution
Problem 67
Graphical Analysis (a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, (c) set \(y=0\) and solve the resulting equation, and (d) compare the result of part (c) with the \(x\) -intercepts of the graph. $$y=x^{4}-10 x^{2}+9$$
4 step solution
Problem 67
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$x^{3}-4 x^{2} \geq 0$$
4 step solution
Problem 67
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$4 x^{2}+16 x+17=0$$
5 step solution
Problem 67
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &x-y=10\\\ &x+2 y=4 \end{aligned}$$
3 step solution
Problem 67
A triangular sail has an area of 182.25 square feet. The sail has a base of 13.5 feet. Find the height of the sail.
3 step solution
Problem 67
Simplify the complex number and write it in standard form. $$-6 i^{3}+i^{2}$$
3 step solution
Problem 68
Graphical Analysis (a) use a graphing utility to graph the equation, (b) use the graph to approximate any \(x\) -intercepts of the graph, (c) set \(y=0\) and solve the resulting equation, and (d) compare the result of part (c) with the \(x\) -intercepts of the graph. $$y=x^{4}-29 x^{2}+100$$
4 step solution
Problem 68
Solve the inequality and graph the solution on the real number line. Use a graphing utility to verify your solution graphically. $$x^{5}-3 x^{4} \leq 0$$
4 step solution
Problem 68
Use the Quadratic Formula to solve the equation. Use a graphing utility to verify your solutions graphically. $$9 x^{2}-6 x+37=0$$
4 step solution
Problem 68
Determine any point(s) of intersection algebraically. Then verify your result numerically by creating a table of values for each function. $$\begin{aligned} &4 x-y=4\\\ &x-4 y=1 \end{aligned}$$
4 step solution