Chapter 2
College Algebra · 450 exercises
Problem 44
What is the total distance that two people travel in 3 \(\mathrm{h}\) if one of them is riding a bike at 15 \(\mathrm{mi} / \mathrm{h}\) and the other is walking at 3 \(\mathrm{mi} / \mathrm{h}\) ?
3 step solution
Problem 44
For the following exercises, use a calculator to help answer the questions. Evaluate \((l+i)^{k}-(l-i)^{k}\) for \(k=4,8\), and 12 . Predict the value for \(k=16\).
4 step solution
Problem 44
enter the expressions into your graphing utility and find the zeroes to the equation (the x-intercepts) by using \(2^{\text { nd }}\) CALC \(2 :\) zero. Recall finding zeroes will ask left bound (move your cursor to the left of the zero, enter), then right bound (move your cursor to the right of the zero, enter), then guess (move your cursor between the bounds near the zero, enter). Round your answers to the nearest thousandth. $$\mathrm{Y}_{1}=4 x^{2}+3 x-2$$
7 step solution
Problem 45
For the following exercises, write the set in interval notation. $$ \\{x | x < 4\\} $$
3 step solution
Problem 45
For the following exercises, solve for the unknown variable. $$ \left|x^{2}+2 x-36\right|=12 $$
4 step solution
Problem 45
Write the set in interval notation. $$ \\{x \mid x<4\\} $$
4 step solution
Problem 45
For the following exercises, find the slope of the lines that pass through each pair of points and determine whether the lines are parallel or perpendicular. \((-1,3)\) and \((5,1)\) \((-2,3)\) and \((0,9)\)
4 step solution
Problem 45
If the area model for a triangle is \(A=\frac{1}{2} b h,\) find the area of a triangle with a height of 16 in. and a base of 11 in.
5 step solution
Problem 45
Enter the expressions into your graphing utility and find the zeroes to the equation (the \(x\) -intercepts) by using \(2^{\text {nd }}\) CALC 2 :zero. Recall finding zeroes will ask left bound (move your cursor to the left of the zero, enter), then right bound (move your cursor to the right of the zero, enter), then guess (move your cursor between the bounds near the zero, enter). Round your answers to the nearest thousandth. $$ \mathrm{Y}_{1}=-3 x^{2}+8 x-1 $$
6 step solution
Problem 45
For each of the following exercises, use the graph in the figure below. Find the distance that \((-3,4)\) is from the origin.
6 step solution
Problem 46
For the following exercises, write the set in interval notation. $$ \\{x | x \text { is all real numbers }\\} $$
3 step solution
Problem 46
For the following exercises, use the model for the period of a pendulum, \(T\), such that \(T=2 \pi \sqrt{\frac{L}{g}}\), where the length of the pendulum is \(L\) and the acceleration due to gravity is \(g\). If the acceleration due to gravity is \(9.8 \mathrm{~m} / \mathrm{s}^{2}\) and the period equals \(1 \mathrm{~s}, \mathrm{fi}\) d the length to the nearest \(\mathrm{cm}\) \((100 \mathrm{~cm}=1 \mathrm{~m})\)
6 step solution
Problem 46
Write the set in interval notation. $$ \\{x \mid x \text { is all real numbers }\\} $$
3 step solution
Problem 46
For the following exercises, find the slope of the lines that pass through each pair of points and determine whether the lines are parallel or perpendicular. \((2,5)\) and \((5,9)\) \((-1,-1)\) and \((2,3)\)
3 step solution
Problem 46
For the following exercises, use a calculator to help answer the questions. Show that a solution of \(x^{8}-1=0\) is \(\frac{\sqrt{2}}{2}+\frac{\sqrt{2}}{2} i\).
3 step solution
Problem 46
Enter the expressions into your graphing utility and find the zeroes to the equation (the \(x\) -intercepts) by using \(2^{\text {nd }}\) CALC 2 :zero. Recall finding zeroes will ask left bound (move your cursor to the left of the zero, enter), then right bound (move your cursor to the right of the zero, enter), then guess (move your cursor between the bounds near the zero, enter). Round your answers to the nearest thousandth. $$ \mathrm{Y}_{1}=0.5 x^{2}+x-7 $$
7 step solution
Problem 46
For each of the following exercises, use the graph in the figure below. Find the distance that \((5,2)\) is from the origin. Round to three decimal places.
6 step solution
Problem 46
Solve for \(h: A=\frac{1}{2} b h\)
3 step solution
Problem 47
For the following exercises, write the interval in set-builder notation. $$ (-\infty, 6) $$
3 step solution
Problem 47
For the following exercises, use the model for the period of a pendulum, \(T\), such that \(T=2 \pi \sqrt{\frac{L}{g}}\), where the length of the pendulum is \(L\) and the acceleration due to gravity is \(g\). If the gravity is \(32 \mathrm{ft} /{ }^{2}\) and the period equals \(1 \mathrm{~s}\), fi d the length to the nearest in. (12 in. = \(1 \mathrm{ft}\) ). Round your answer to the nearest in.
6 step solution
Problem 47
Write the interval in set-builder notation. $$ (-\infty, 6) $$
3 step solution
Problem 47
For the following exercises, express the equations in slope intercept form (rounding each number to the thousandths place). Enter this into a graphing calculator as Y1, then adjust the ymin and ymax values for your window to include where the y-intercept occurs. State your ymin and ymax values. \(0.537 x-2.19 y=100\)
5 step solution
Problem 47
For the following exercises, evaluate the expressions, writing the result as a simplified complex number. $$ \frac{1}{i}+\frac{4}{i^{3}} $$
5 step solution
Problem 47
To solve the quadratic equation \(x^{2}+5 x-7=4,\) we can graph these two equations \(\mathrm{Y}_{1}=x^{2}+5 x-7 \qquad \mathrm{Y}_{2}=4\) and find the points of intersection. Recall \(2^{\text { nd }} \mathrm{CALC} \) 5 intersection. Do this and find the solutions to the nearest tenth.
5 step solution
Problem 48
For the following exercises, write the interval in set-builder notation. $$ (4, \infty) $$
2 step solution
Problem 48
Write the interval in set-builder notation. $$ (4, \infty) $$
4 step solution
Problem 48
For the following exercises, express the equations in slope intercept form (rounding each number to the thousandths place). Enter this into a graphing calculator as Y1, then adjust the ymin and ymax values for your window to include where the y-intercept occurs. State your ymin and ymax values. \(4,500 x-200 y=9,528\)
4 step solution
Problem 48
For the following exercises, use a model for body surface area, BSA, such that \(B S A=\sqrt{\frac{w h}{3600}},\) where \(w=\) weight in \(\mathrm{kg}\) and \(h=\) height in \(\mathrm{cm} .\) Find the height of a 72 -kg female to the nearest cm whose \(B S A=1.8 .\)
6 step solution
Problem 48
The volume formula for a cylinder is \(V=\pi r^{2} h\) Using the symbol \(\pi\) in your answer, find the volume of a cylinder with a radius, \(r,\) of 4 \(\mathrm{cm}\) and a height of 14 \(\mathrm{cm} .\)
6 step solution
Problem 48
For the following exercises, evaluate the expressions, writing the result as a simplified complex number. $$ \frac{1}{i^{11}}-\frac{1}{i^{21}} $$
5 step solution
Problem 48
To solve the quadratic equation \(0.3 x^{2}+2 x-4=2\) , we can graph these two equations \(\mathrm{Y}_{1}=0.3 x^{2}+2 x-4 \qquad \mathrm{Y}_{2}=2\) and find the points of intersewction. Recall \(2^{\text { nd }} \mathrm{CALC}\) 5 intersection. Do this and find the solutions to the nearest tenth.
4 step solution
Problem 48
After graphing it, use the \(2^{\text {nd }}\) CALC button and 1:value button, hit ENTER. At the lower part of the screen you will see " \(\mathbf{x}=\) " and a blinking cursor. You may enter any number for \(x\) and it will display the \(y\) value for any \(x\) value you input. Use this and plug in \(x=0\), thus finding the \(y\) -intercept, for each of the following graphs. $$ Y_{1}=-2 x+5 $$
5 step solution
Problem 49
For the following exercises, write the interval in set-builder notation. $$ [-3,5) $$
2 step solution
Problem 49
Write the interval in set-builder notation. $$ [-3,5) $$
3 step solution
Problem 49
For the following exercises, express the equations in slope intercept form (rounding each number to the thousandths place). Enter this into a graphing calculator as Y1, then adjust the ymin and ymax values for your window to include where the y-intercept occurs. State your ymin and ymax values. \(\frac{200-30 y}{x}=70\)
6 step solution
Problem 49
For the following exercises, use a model for body surface area, BSA, such that \(B S A=\sqrt{\frac{w h}{3600}},\) where \(w=\) weight in \(\mathrm{kg}\) and \(h=\) height in \(\mathrm{cm} .\) Find the weight of a 177 -cm male to the nearest kg whose \(B S A=2.1 .\)
7 step solution
Problem 49
For the following exercises, evaluate the expressions, writing the result as a simplified complex number. $$ i^{7}\left(1+i^{2}\right) $$
4 step solution
Problem 49
Solve for \(h : V=\pi r^{2} h\)
3 step solution
Problem 49
Beginning with the general form of a quadratic equation, \(a x^{2}+b x+c=0,\) solve for \(x\) by using the completing the square method, thus deriving the quadratic formula.
8 step solution
Problem 49
After graphing it, use the \(2^{\text {nd }}\) CALC button and 1:value button, hit ENTER. At the lower part of the screen you will see " \(\mathbf{x}=\) " and a blinking cursor. You may enter any number for \(x\) and it will display the \(y\) value for any \(x\) value you input. Use this and plug in \(x=0\), thus finding the \(y\) -intercept, for each of the following graphs. $$ \mathrm{Y}_{1}=\frac{3 x-8}{4} $$
3 step solution
Problem 50
For the following exercises, write the interval in set-builder notation. $$ [-4,1] \cup[9, \infty) $$
4 step solution
Problem 50
Write the interval in set-builder notation. $$ [-4,1] \cup[9, \infty) $$
3 step solution
Problem 50
Starting with the point-slope formula \(y-y_{1}=m\left(x-x_{1}\right),\) solve this expression for \(x\) in terms of \(x_{1}, y, y_{1},\) and \(m .\)
4 step solution
Problem 50
For the following exercises, evaluate the expressions, writing the result as a simplified complex number. $$ i^{-3}+5 i^{7} $$
4 step solution
Problem 50
Show that the sum of the two solutions to the quadratic equation is \(-\frac{b}{a}\) .
6 step solution
Problem 50
After graphing it, use the \(2^{\text {nd }}\) CALC button and 1:value button, hit ENTER. At the lower part of the screen you will see " \(\mathbf{x}=\) " and a blinking cursor. You may enter any number for \(x\) and it will display the \(y\) value for any \(x\) value you input. Use this and plug in \(x=0\), thus finding the \(y\) -intercept, for each of the following graphs. $$ \mathrm{Y}_{1}=\frac{x+5}{2} $$
5 step solution
Problem 51
Starting with the standard form of an equation \(A x+B y=C,\) solve this expression for \(y\) in terms of \(A, B, C,\) and \(x .\) Then put the expression in slope-intercept form.
4 step solution
Problem 51
Solve for \(r : V=\pi r^{2} h\)
4 step solution
Problem 51
For the following exercises, evaluate the expressions, writing the result as a simplified complex number. $$ \frac{(2+i)(4-2 i)}{(1+i)} $$
4 step solution
Problem 51
A person has a garden that has a length 10 feet longer than the width. Set up a quadratic equation to find the dimensions of the garden if its area is 119 \(\mathrm{ft}^{2}\) . Solve the quadratic equation to find the length and width.
7 step solution