Chapter 1

Contemporary Precalculus · 341 exercises

Problem 1

Solve the equation. $$3 x+2=26$$

2 step solution

Problem 2

Find the coordinates of the point \(P .\). \(P\) lies 4 units to the left of the \(y\) -axis and 5 units below the \(x\) -axis.

3 step solution

Problem 2

Use your calculator to determine which of the following rational numbers is the best approximation of the irrational number \(\pi\) $$\frac{22}{7}, \quad \frac{355}{113}, \quad \frac{103,993}{33,102}, \quad \frac{2,508,429,787}{798,458,000}$$ If your calculator says that one of these numbers equals \(\pi\) it's lying. All you can conclude is that the number agrees with \(\pi\) for as many decimal places as your calculator can handle (usually \(12-14\) ).

3 step solution

Problem 2

Solve the equation. $$\frac{y}{5}-3=14$$

3 step solution

Problem 3

Find the slope of the line through the given points. $$(1,2)$;(3,7)$$

4 step solution

Problem 3

Find the coordinates of the point \(P .\). \(P\) lies 3 units above the \(x\) -axis and on the same vertical line as (-6,7).

3 step solution

Problem 3

\(b, c,\) and \(d\) are real numbers such that \(b<0\) \(c>0,\) and \(d<0 .\) Determine whether the given number is positive or negative. $$-b$$

3 step solution

Problem 3

Solve the equation. $$3 x+2=9 x+7$$

3 step solution

Problem 4

Find the slope of the line through the given points. $$(-1,-2)$;(2,-1)$$

4 step solution

Problem 4

Solve the equation. $$-7(t+2)=3(4 t+1)$$

4 step solution

Problem 5

Find the slope of the line through the given points. $$(1 / 4,0) ;(3 / 4,2)$$

4 step solution

Problem 5

Find the coordinates of the point \(P .\). \(P\) lies 4 units to the right of the \(y\) -axis, and its \(y\) -coordinate is half its \(x\) -coordinate.

3 step solution

Problem 5

\(b, c,\) and \(d\) are real numbers such that \(b<0\) \(c>0,\) and \(d<0 .\) Determine whether the given number is positive or negative. $$b c d$$

3 step solution

Problem 5

Solve the equation. $$\frac{3 y}{4}-6=y+2$$

4 step solution

Problem 6

Find the slope of the line through the given points. $$(\sqrt{2},-1) ;(2,-9)$$

5 step solution

Problem 6

Solve the equation. $$2(1+x)=3 x+5$$

3 step solution

Problem 7

Find a number t such that the line passing through the two given points has slope -2. $$(0, t) ;(9,4)$$

3 step solution

Problem 7

Sketch a scatter plot and a line graph of the given data. The table shows sales of personal digital video recorders.* Let \(x=0\) correspond to \(2000,\) and measure \(y\) in thousands. $$\begin{array}{|c|c|}\hline \text { Year } & \text { Number Sold } \\\\\hline 2000 & 257,000 \\\\\hline 2001 & 129,000 \\ \hline 2002 & 143,000 \\\\\hline 2003 & 214,000 \\\\\hline 2004 & 315,000 \\\\\hline 2005 & 485,000 \\\\\hline \end{array}$$

4 step solution

Problem 7

\(b, c,\) and \(d\) are real numbers such that \(b<0\) \(c>0,\) and \(d<0 .\) Determine whether the given number is positive or negative. $$b c-b d$$

3 step solution

Problem 7

Solve the equation for the indicated variable. $$x=3 y-5 \text { for } y$$

5 step solution

Problem 8

Sketch a scatter plot and a line graph of the given data. The maximum yearly contribution to an individual retirement account (IRA) was \(\$ 3000\) in \(2003 .\) It changed to \(\$ 4000\) in 2005 and will change to \(\$ 5000\) in \(2008 .\) Assuming \(3 \%\) inflation, however, the picture is somewhat different. The table shows the maximum IRA contribution in fixed 2003 dollars. Let \(x=0\) correspond to 2000. $$\begin{array}{|c|c|}\hline \text { Year } & \text { Maximum Contribution } \\\\\hline 2003 & 3000 \\\\\hline 2004 & 2910 \\\\\hline 2005 & 3764 \\\\\hline 2006 & 3651 \\\\\hline 2007 & 3541 \\\\\hline 2008 & 4294 \\\\\hline\end{array}$$

2 step solution

Problem 8

Find a number t such that the line passing through the two given points has slope -2. $$(1, t) ;(-2,4)$$

5 step solution

Problem 8

Solve the equation for the indicated variable. $$5 x-2 y=1 \text { for } x$$

4 step solution

Problem 9

(a) If the first coordinate of a point is greater than 3 and its second coordinate is negative, in what quadrant does it lie? (b) What is the answer in part (a) if the first coordinate is less than \(3 ?\)

2 step solution

Problem 9

Find a number t such that the line passing through the two given points has slope -2. $$(t+1,5) ;(6,-3 t+7)$$

5 step solution

Problem 9

Use a calculator and list the given numbers in order from smallest to largest. $$\frac{189}{37}, \frac{4587}{691}, \quad \sqrt{47}, \quad 6.735, \quad \sqrt{27}, \quad \frac{2040}{523}$$

5 step solution

Problem 9

Solve the equation for the indicated variable. $$A=\frac{h}{2}(b+c) \quad \text { for } b$$

6 step solution

Problem 10

In what quadrant(s) does a point lie if the product of its coordinates is (a) positive? (b) negative?

2 step solution

Problem 10

Use a calculator and list the given numbers in order from smallest to largest. $$\frac{385}{177}, \quad \sqrt{10}, \quad \frac{187}{63}, \quad \pi, \quad \sqrt{\sqrt{85}}, \quad 2.9884$$

3 step solution

Problem 10

Solve the equation for the indicated variable. $$V=\pi b^{2} c \quad \text { for } c$$

4 step solution

Problem 11

Let \(L\) be a nonvertical straight line through the origin. \(L\) intersects the vertical line through (1, 0) at a point P. Show that the second coordinate of \(P\) is the slope of \(L\).

4 step solution

Problem 11

Express the given statement in symbols. -4 is greater than -8

3 step solution

Problem 11

Solve the equation for the indicated variable. $$V=\frac{\pi d^{2} h}{4} \text { for } h$$

3 step solution

Problem 12

(a) Plot the points \((5,3),(4,-2),(-1,4),\) and (-3,-5) (b) Change the sign of the \(x\) -coordinate in each of the points in part (a), and plot these new points. (c) Explain how the points \((a, b)\) and \((-a, b)\) are related graphically. [Hint: What are their relative positions with respect to the \(y\) -axis?]

5 step solution

Problem 12

Express the given statement in symbols. -17 is less than 6

3 step solution

Problem 12

Solve the equation for the indicated variable. $$\frac{1}{r}=\frac{1}{s}+\frac{1}{t} \quad \text { for } r$$

6 step solution

Problem 13

Find the distance between the two points and the midpoint of the segment joining them. $$(-3,5),(2,-7)$$

5 step solution

Problem 13

Express the given statement in symbols. \(\pi\) is less than 100

3 step solution

Problem 13

Solve the equation by factoring. $$x^{2}-8 x+15=0$$

4 step solution

Problem 14

Find the distance between the two points and the midpoint of the segment joining them. $$(2,4),(3,6)$$

5 step solution

Problem 14

Express the given statement in symbols. \(x\) is nonnegative.

2 step solution

Problem 14

Solve the equation by factoring. $$x^{2}-5 x+6=0$$

5 step solution

Problem 15

Find the distance between the two points and the midpoint of the segment joining them. $$(-2,5),(-1,2)$$

3 step solution

Problem 15

Express the given statement in symbols. \(z\) is greater than or equal to -4

3 step solution

Problem 15

Solve the equation by factoring. $$x^{2}-5 x=14$$

4 step solution

Problem 16

Find the distance between the two points and the midpoint of the segment joining them. $$(-2,3),(-3,2)$$

5 step solution

Problem 16

Express the given statement in symbols. \(t\) is negative.

2 step solution

Problem 16

Solve the equation by factoring. $$x^{2}+x=20$$

3 step solution

Problem 17

Find the equation of the line with y-intercept b and slope \(m\). $$b=5, m=4$$

3 step solution

Problem 17

Find the distance between the two points and the midpoint of the segment joining them. $$(\sqrt{2}, 1),(\sqrt{3}, 2)$$

5 step solution

Show/ page