Chapter 1
Algebra for College Students · 399 exercises
Problem 1
Determine whether each statement is true or false. If it is false, explain why. The union of the solution sets of \(x+1=6, x+1<6,\) and \(x+1>6\) is \((-\infty, \infty)\)
5 step solution
Problem 1
Complete each statement. The following key terms may be used once, more than once, or not at all. $$\begin{array}{cc}\text{linear equation}&\text{solution}&\text{algebraic expression}&\text{contradiction}& \text{all real numbers}\\\ \text{solution set}&\text{identity}&\text{conditional equation}&\text{first-degree equation }&\text{empty set}\varnothing \end{array}$$ A collection of numbers, variables, operation symbols, and grouping symbols, such as \(2(8 x-15),\) is a \((n)\) __________. While an equation (does/does not) include an equality symbol, there (is / is not) an equality symbol in an algebraic expression.
3 step solution
Problem 1
In each of the following, translate part (a) as an expression and translate part (b) as an equation or inequality. Use \(x\) to represent the number. (a) 15 more than a number (b) 15 is more than a number.
2 step solution
Problem 2
The distance between Cape Town, South Africa, and Miami is \(7700 \mathrm{mi}\). If a jet averages 550 mph between the two cities, what is its travel time in hours?
4 step solution
Problem 2
In each of the following, translate part (a) as an expression and translate part (b) as an equation or inequality. Use \(x\) to represent the number. (a) 5 greater than a number (b) 5 is greater than a number.
2 step solution
Problem 3
How many solutions will \(|a x+b|=k\) have for each situation? (a) \(k=0\) (b) \(k>0\) (c) \(k<0\)
4 step solution
Problem 3
Work each problem to review converting between decimals and percents. Write each decimal as a percent. (a) 0.35 (b) 0.18 (c) 0.02 (d) 0.075 (e) 1.5
6 step solution
Problem 3
Complete each statement. The following key terms may be used once, more than once, or not at all. $$\begin{array}{cc}\text{linear equation}&\text{solution}&\text{algebraic expression}&\text{contradiction}& \text{all real numbers}\\\ \text{solution set}&\text{identity}&\text{conditional equation}&\text{first-degree equation }&\text{empty set}\varnothing \end{array}$$ If we let \(x=2\) in the linear equation \(2 x+5=9,\) a (true/false) statement results. The number 2 is a(n) __________ of the equation, and \\{2\\} is the ____________.
4 step solution
Problem 3
Tri traveled from Chicago to Des Moines, a distance of \(300 \mathrm{mi}\), in \(10 \mathrm{hr}\). What was his rate in miles per hour?
4 step solution
Problem 3
In each of the following, translate part (a) as an expression and translate part (b) as an equation or inequality. Use \(x\) to represent the number. (a) 8 less than a number (b) 8 is less than a number.
4 step solution
Problem 4
Work each problem to review converting between decimals and percents. Write each percent as a decimal. (a) \(60 \%\) (b) \(37 \%\) (c) \(8 \%\) (d) \(3.5 \%\) (e) \(210 \%\)
6 step solution
Problem 4
Determine whether each statement is true or false. If it is false, explain why. The intersection of the sets \((-\infty, 7]\) and \([7, \infty)\) is \\{7\\} .
3 step solution
Problem 4
Complete each statement. The following key terms may be used once, more than once, or not at all. $$\begin{array}{cc}\text{linear equation}&\text{solution}&\text{algebraic expression}&\text{contradiction}& \text{all real numbers}\\\ \text{solution set}&\text{identity}&\text{conditional equation}&\text{first-degree equation }&\text{empty set}\varnothing \end{array}$$ A linear equation with one solution in its ____________, such as \(2 x+5=9,\) is \(\mathrm{a}(\mathrm{n})\) ___________.
3 step solution
Problem 4
In each of the following, translate part (a) as an expression and translate part (b) as an equation or inequality. Use \(x\) to represent the number. (a) 6 less than a number (b) 6 is less than a number.
2 step solution
Problem 4
A square has perimeter 160 in. What would be the perimeter of an equilateral triangle whose sides each measure the same length as the side of the square?
3 step solution
Problem 5
Solve each equation. $$ |x|=12 $$
4 step solution
Problem 5
Solve each formula for the specified variable. \(I=p r t\) for \(r \quad\) (simple interest)
4 step solution
Problem 5
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ A \cap D $$
4 step solution
Problem 5
An equilateral triangle has perimeter 27 in. What would be the area of a square whose sides each measure the same length as the side of the equilateral triangle?
3 step solution
Problem 6
Solve each equation. $$ |x|=14 $$
4 step solution
Problem 6
Solve each formula for the specified variable. \(d=r t\) for \(t \quad(\) distance \()\)
4 step solution
Problem 6
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ B \cap C $$
5 step solution
Problem 6
A student translated the phrase "the quotient of a number \(n\) and \(12^{\prime \prime}\) incorrectly as \(\frac{12}{n}\).Give the correct mathematical expression.
4 step solution
Problem 6
A circle has area \(25 \pi \mathrm{ft}^{2}\). What would be the perimeter of a square whose sides each measure the same length as the radius of the circle?
3 step solution
Problem 7
Solve each equation. $$ |4 x|=20 $$
3 step solution
Problem 7
Solve each formula for the specified variable. \(\mathscr{A}=L W \quad\) (area of a rectangle) (a) for \(W\) (b) for \(L\)
3 step solution
Problem 7
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ B \cap A $$
5 step solution
Problem 7
Which equations are linear equations in \(x ?\) A. \(3 x+x-2=0\) B. \(12=x^{2}\) C. \(9 x-4=9\) D. \(3 x+2 y=6\)
5 step solution
Problem 7
Translate each verbal phrase into \(a\) mathematical expression using \(x\) as the variable. $$ \text { Twice a number, decreased by } 13 $$
3 step solution
Problem 8
Solve each equation. $$ |5 x|=30 $$
5 step solution
Problem 8
Solve each formula for the specified variable. \(\mathscr{A}=b h \quad\) (area of a parallelogram) (a) for \(b\) (b) for \(h\)
4 step solution
Problem 8
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ C \cap A $$
4 step solution
Problem 8
Translate each verbal phrase into \(a\) mathematical expression using \(x\) as the variable. $$ \text { Triple a number, decreased by } 14 $$
4 step solution
Problem 9
Solve each equation. $$ |x-3|=9 $$
5 step solution
Problem 9
Solve each formula for the specified variable. \(P=2 L+2 W\) for \(L\) (perimeter of a rectangle)
4 step solution
Problem 9
Determine whether each of the following is an expression or an equation. \(-3 x+2-4=x\)
3 step solution
Problem 9
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ B \cap \varnothing $$
4 step solution
Problem 9
Translate each verbal phrase into \(a\) mathematical expression using \(x\) as the variable. $$ 12 \text { increased by four times a number } $$
3 step solution
Problem 9
Otis has a box of coins that he uses when he plays poker with his friends. The box contains 44 coins, consisting of pennies, dimes, and quarters. The number of pennies is equal to the number of dimes. The total value is \(\$ 4.37 .\) How many of each denomination of coin does he have in the box?
6 step solution
Problem 10
Solve each equation. $$ |x-5|=13 $$
5 step solution
Problem 10
Solve each formula for the specified variable. \(P=a+b+c \quad\) (perimeter of a triangle) (a) for \(b\) (b) for \(c\)
3 step solution
Problem 10
\(\quad\) A student solved the following inequality incorrectly as shown. $$ \begin{array}{l} -2 x<-18 \\ \frac{-2 x}{-2}<\frac{-18}{-2} \end{array} $$ $$ x<9 \quad(-\infty, 9) $$ WHAT WENT WRONG? Give the correct solution set.
4 step solution
Problem 10
Determine whether each of the following is an expression or an equation. \(-3 x+2-4-x=4\)
3 step solution
Problem 10
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ A \cap \varnothing $$
3 step solution
Problem 10
Translate each verbal phrase into \(a\) mathematical expression using \(x\) as the variable. $$ 15 \text { more than one-half of a number } $$
3 step solution
Problem 10
Nana found some coins under her sofa pillows. There were equal numbers of nickels and quarters and twice as many half-dollars as quarters. If she found \(\$ 2.60\) in all, how many of each denomination of coin did she find?
5 step solution
Problem 11
Solve each equation. $$ |2 x-1|=11 $$
4 step solution
Problem 11
Solve each formula for the specified variable. \(V=L W H\) (volume of a rectangular solid) (a) for \(W\) (b) for \(H\)
5 step solution
Problem 11
Let \(A=\\{1,2,3,4,5,6\\}, B=\\{1,3,5\\}, C=\\{1,6\\},\) and \(D=\\{4\\} .\) Find each set. $$ A \cup B $$
4 step solution
Problem 11
Determine whether each of the following is an expression or an equation. \(4(x+3)-2(x+1)-10\)
4 step solution