Chapter 2

Algebra and Trigonometry Real Mathematics, Real People · 560 exercises

Problem 18

Write the complex number in standard form. $$-i-(\sqrt{-23})^{2}$$

3 step solution

Problem 18

Determine whether the equation is an identity, a conditional equation, or a contradiction. $$\frac{5}{x}+\frac{3}{x}=24$$

4 step solution

Problem 19

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{x-10}-4=0$$

4 step solution

Problem 19

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$4 x+7<3+2 x$$

3 step solution

Problem 19

Use a graphing utility to graph the equation and approximate any \(x\) - and \(y\) -intercepts. Verify your results algebraically. $$y=20-(3 x-10)$$

5 step solution

Problem 19

Write the complex number in standard form. $$\sqrt{-0.09}$$

3 step solution

Problem 19

Solve the equation using two methods. Then explain which method you prefer. $$\frac{3 x}{8}-\frac{4 x}{3}=4$$

3 step solution

Problem 20

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$3 x+1 \geq 2+x$$

4 step solution

Problem 20

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{2 x+5}+3=0$$

4 step solution

Problem 20

Solve the quadratic equation by factoring. Check your solutions in the original equation. $$x^{2}+2 a x+a^{2}=0$$

4 step solution

Problem 20

Use a graphing utility to graph the equation and approximate any \(x\) - and \(y\) -intercepts. Verify your results algebraically. $$y=10+2(x-2)$$

4 step solution

Problem 20

Write the complex number in standard form. $$\sqrt{-0.0004}$$

3 step solution

Problem 20

Solve the equation using two methods. Then explain which method you prefer. $$\frac{3 z}{8}-\frac{z}{10}=6$$

4 step solution

Problem 21

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$2(1-x)<3 x+7$$

4 step solution

Problem 21

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt[3]{6 x}+9=0$$

4 step solution

Problem 21

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$x^{2}=49$$

3 step solution

Problem 21

The zero(s) of the function are given. Verify the zero(s) both algebraically and graphically. \(Function\) \(f(x)=4(3-x)\) \(Z e r o(s)\) \(x=3\)

2 step solution

Problem 21

Perform the addition or subtraction and write the result in standard form. $$(4+i)-(7-2 i)$$

3 step solution

Problem 21

Solve the equation using two methods. Then explain which method you prefer. $$\frac{2 x}{5}+5 x=\frac{4}{3}$$

3 step solution

Problem 22

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$2 x+7<3(x-4)$$

5 step solution

Problem 22

Find all solutions of the equation algebraically. Check your solutions. $$2 \sqrt[3]{x}-10=0$$

4 step solution

Problem 22

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$x^{2}=144$$

4 step solution

Problem 22

Perform the addition or subtraction and write the result in standard form. $$(11-2 i)-(-3+6 i)$$

3 step solution

Problem 22

Solve the equation using two methods. Then explain which method you prefer. $$\frac{4 y}{3}-2 y=\frac{16}{5}$$

3 step solution

Problem 23

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$\frac{3}{4} x-6 \leq x-7$$

3 step solution

Problem 23

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt[3]{2 x+1}+8=0$$

4 step solution

Problem 23

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$3 x^{2}=81$$

3 step solution

Problem 23

The zero(s) of the function are given. Verify the zero(s) both algebraically and graphically. \(Function\) \(f(x)=x^{3}-6 x^{2}+5 x\) \(Z e r o(s)\) \(x=0,5,1\)

2 step solution

Problem 23

Perform the addition or subtraction and write the result in standard form. $$13 i-(14-7 i)$$

3 step solution

Problem 23

Solve the equation (if possible). $$3 x-5=2 x+7$$

2 step solution

Problem 24

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$3+\frac{2}{7} x>x-2$$

4 step solution

Problem 24

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt[3]{4 x-3}+2=0$$

4 step solution

Problem 24

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$9 x^{2}=36$$

4 step solution

Problem 24

The zero(s) of the function are given. Verify the zero(s) both algebraically and graphically. \(Function\) \(f(x)=x^{3}-9 x^{2}+18 x\) \(Z e r o(s)\) \(x=0,3,6\)

3 step solution

Problem 24

Perform the addition or subtraction and write the result in standard form. $$22+(-5+8 i)-9 i$$

3 step solution

Problem 24

Solve the equation (if possible). $$5 x+3=6-2 x$$

3 step solution

Problem 25

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$1 \leq 2 x+3 \leq 9$$

5 step solution

Problem 25

Find all solutions of the equation algebraically. Check your solutions. $$\sqrt{5 x-26}+4=x$$

5 step solution

Problem 25

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$x^{2}+12=112$$

4 step solution

Problem 25

The zero(s) of the function are given. Verify the zero(s) both algebraically and graphically. \(Function\) \(f(x)=\frac{x+1}{2}-\frac{x-2}{7}+1\) \(Z e r o(s)\) \(x=-5\)

3 step solution

Problem 25

Perform the addition or subtraction and write the result in standard form. $$\left(\frac{3}{2}+\frac{5}{2} i\right)+\left(\frac{5}{3}+\frac{11}{3} i\right)$$

4 step solution

Problem 25

Solve the equation (if possible). $$3(y-5)=3+5 y$$

3 step solution

Problem 26

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$-8 \leq-3 x+5<13$$

4 step solution

Problem 26

Find all solutions of the equation algebraically. Check your solutions. $$x-\sqrt{8 x-31}=5$$

4 step solution

Problem 26

Solve the equation by extracting square roots. List both the exact solutions and the decimal solutions rounded to the nearest hundredth. $$x^{2}-3=78$$

3 step solution

Problem 26

The zero(s) of the function are given. Verify the zero(s) both algebraically and graphically. \(Function\) \(f(x)=x-3-\frac{10}{x}\) \(Z e r o(s)\) \(x=-2,5\)

3 step solution

Problem 26

Perform the addition or subtraction and write the result in standard form. $$\left(\frac{3}{4}+\frac{7}{5} i\right)-\left(\frac{5}{6}-\frac{1}{6} i\right)$$

4 step solution

Problem 26

Solve the equation (if possible). $$4(z-3)+3 z=1+8 z$$

3 step solution

Problem 27

The following ordered pairs \((t, T)\) represent the Olympic year \(t\) and the winning time \(T\) (in minutes) in the women's 400 -meter freestyle swimming event. $$\begin{aligned} &(1956,4.91)\\\ &(1960,4.84)\\\ &(1964,4.72)\\\ &(1968,4.53)\\\ &(1972,4.32)\\\ &(1976,4.16)\\\ &(1980,4.15)\\\ &(1984,4.12) \end{aligned}$$ $$\begin{aligned} &(1988,4.06)\\\ &(1992,4.12)\\\ &(1996,4.12)\\\ &(2000,4.10)\\\ &(2004,4.09)\\\ &(2008,4.05)\\\ &(2012,4.02) \end{aligned}$$ (a) Use the regression feature of a graphing utility to find a linear model for the data and to identify the correlation coefficient. Let \(t\) represent the year, with \(t=0\) corresponding to 1950 (b) What information is given by the sign of the slope of the model? (c) Use the graphing utility to plot the data and graph the model in the same viewing window. (d) Create a table showing the actual values of \(y\) and the values of \(y\) given by the model. How closely does the model fit the data? (e) How can you use the value of the correlation coefficient to help answer the question in part (d)? (f) Would you use the model to predict the winning times in the future? Explain.

7 step solution

Problem 27

Solve the inequality and sketch the solution on the real number line. Use a graphing utility to verify your solution graphically. $$-8 \leq 1-3(x-2)<13$$

3 step solution

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