Chapter 2
Algebra and Trigonometry Real Mathematics, Real People · 560 exercises
Problem 27
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x+1}-3 x=1$$
6 step solution
Problem 27
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(x-12)^{2}=16$$
3 step solution
Problem 27
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$2.7 x-0.4 x=1.2$$
5 step solution
Problem 27
Perform the addition or subtraction and write the result in standard form. $$(1.6+3.2 i)+(-5.8+4.3 i)$$
4 step solution
Problem 27
Solve the equation (if possible). $$\frac{x}{5}-\frac{x}{2}=3$$
2 step solution
Problem 28
In a study, 60 colts were measured every 14 days from birth. The ordered pairs \((d, l)\) represent the average length \(l\) (in centimeters) of the 60 colts \(d\) days after birth. (Spreadsheet at LarsonPrecalculus.com) $$\begin{aligned} &(14,81.2)\\\ &(56,98.3)\\\ &(98,110.0) \end{aligned}$$ $$\begin{aligned} &(28,87.1)\\\ &(70,102.4) \end{aligned}$$ $$\begin{aligned} &(42,93.7)\\\ &(84,106.2) \end{aligned}$$ (a) Use the regression feature of a graphing utility to find a linear model for the data and to identify the correlation coefficient. (b) According to the correlation coefficient, does the model represent the data well? Explain. (c) Use the graphing utility to plot the data and graph the model in the same viewing window. How closely does the model fit the data? (d) Use the model to predict the average length of a colt 112 days after birth.
4 step solution
Problem 28
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$0 \leq 2-3(x+1)<20$$
6 step solution
Problem 28
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x+5}-2 x=3$$
5 step solution
Problem 28
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(x-5)^{2}=25$$
3 step solution
Problem 28
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$3.6 x-8.2=0.5 x$$
5 step solution
Problem 28
Perform the addition or subtraction and write the result in standard form. $$-(-3.7-12.8 i)-(6.1-16.3 i)$$
3 step solution
Problem 28
Solve the equation (if possible). $$\frac{3 x}{4}+\frac{x}{2}=-5$$
3 step solution
Problem 29
Determine whether the statement is true or false. Justify your answer. A linear regression model with a positive correlation will have a slope that is greater than \(0 .\)
3 step solution
Problem 29
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$-4<\frac{2 x-3}{3}<4$$
5 step solution
Problem 29
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x+1}=\sqrt{3 x+1}$$
5 step solution
Problem 29
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(3 x-1)^{2}+6=0$$
4 step solution
Problem 29
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$12(x+2)=15(x-4)-3$$
4 step solution
Problem 29
Perform the addition or subtraction and write the result in standard form. $$(5+\sqrt{-27})-(-12+\sqrt{-48})$$
3 step solution
Problem 29
Solve the equation (if possible). $$\frac{5 x-4}{5 x+4}=\frac{2}{3}$$
4 step solution
Problem 30
Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$0 \leq \frac{x+3}{2}<5$$
4 step solution
Problem 30
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x+5}=\sqrt{2 x-5}$$
4 step solution
Problem 30
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(2 x+3)^{2}+25=0$$
3 step solution
Problem 30
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$1200=300+2(x-500)$$
3 step solution
Problem 30
Perform the addition or subtraction and write the result in standard form. $$(7+\sqrt{-18})+(3+\sqrt{-32})$$
3 step solution
Problem 30
Solve the equation (if possible). $$\frac{10 x+3}{5 x+6}=\frac{1}{2}$$
3 step solution
Problem 31
Use your school's library, the Internet, or some other reference source to locate data that you think describe a linear relationship. Create a scatter plot of the data and find the least squares regression line that represents the points. Interpret the slope and \(y\) -intercept in the context of the data. Write a summary of your findings.
5 step solution
Problem 31
Use a graphing utility to approximate the solution. $$5-2 x \geq 1$$
4 step solution
Problem 31
Find all solutions of the equation algebraically. Check your solutions. $$2 x+9 \sqrt{x}-5=0$$
6 step solution
Problem 31
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(x-7)^{2}=(x+3)^{2}$$
4 step solution
Problem 31
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$\frac{3 x}{2}+\frac{1}{4}(x+2)=10$$
4 step solution
Problem 31
Perform the operation and write the result in standard form. $$\sqrt{-6} \cdot \sqrt{-2}$$
3 step solution
Problem 31
Solve the equation (if possible). $$\frac{2}{5}(z-4)+\frac{3 z}{10}=4 z$$
3 step solution
Problem 32
Find all solutions of the equation algebraically. Check your solutions. $$6 x-7 \sqrt{x}-3=0$$
5 step solution
Problem 32
Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$(x+5)^{2}=(x+4)^{2}$$
4 step solution
Problem 32
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$\frac{2 x}{3}+\frac{1}{2}(x-5)=6$$
5 step solution
Problem 32
Perform the operation and write the result in standard form. $$\sqrt{-5} \cdot \sqrt{-10}$$
3 step solution
Problem 32
Solve the equation (if possible). $$\frac{3 x}{2}+\frac{1}{4}(x-2)=10$$
4 step solution
Problem 33
Evaluate the function at each value of the independent variable and simplify. \(f(x)=2 x^{2}-3 x+5\) (a) \(f(-1)\) (b) \(f(w+2)\)
4 step solution
Problem 33
Use a graphing utility to approximate the solution.
$$3(x+1)
4 step solution
Problem 33
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x}-\sqrt{x-5}=1$$
6 step solution
Problem 33
Solve the quadratic equation by completing the square. Verify your answer graphically. $$x^{2}+4 x-32=0$$
5 step solution
Problem 33
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$0.60 x+0.40(100-x)=1.2$$
4 step solution
Problem 33
Perform the operation and write the result in standard form. $$(\sqrt{-10})^{2}$$
3 step solution
Problem 33
Solve the equation (if possible). $$\frac{17+y}{y}+\frac{32+y}{y}=100$$
3 step solution
Problem 34
Evaluate the function at each value of the independent variable and simplify. \(g(x)=5 x^{2}-6 x+1\) (a) \(g(-2)\) (b) \(g(z-2)\)
2 step solution
Problem 34
Use a graphing utility to approximate the solution. $$4(x-3)>8-x$$
4 step solution
Problem 34
Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x}+\sqrt{x-20}=10$$
5 step solution
Problem 34
Solve the quadratic equation by completing the square. Verify your answer graphically. $$x^{2}-2 x-3=0$$
5 step solution
Problem 34
Solve the equation algebraically. Then write the equation in the form \(f(x)=0\) and use a graphing utility to verify the algebraic solution. $$0.75 x+0.2(80-x)=3.9$$
6 step solution
Problem 34
Perform the operation and write the result in standard form. $$(\sqrt{-75})^{2}$$
3 step solution