Question 1

Given the cost function, C(x), and the revenue function, R(x), find the number of units x that must be sold to break even.
-$\begin{array} { l } 
C ( x ) = 2000 x + 66,000 \
R ( x ) = 8000 x
\end{array}$

Accepted Answer

A)  5 units 
B)  13 units 
C)  12 units 
D)  11 units 
A)  5 units 
B)  13 units 
C)  12 units 
D)  11 units

Question 2

Solve the system of equations by the substitution method.
-$\left\{ \begin{array} { l } 
x + 8 y = - 7 \
- 7 x + 7 y = - 77
\end{array} \right.$

Accepted Answer

A)  $( - 9 , - 1 )$ 
B)  $( 8 , - 1 )$ 
C)  no solution 
D)  $( 9 , - 2 )$ 
A)  $( - 9 , - 1 )$ 
B)  $( 8 , - 1 )$ 
C)  no solution 
D)  $( 9 , - 2 )$

Question 3

Solve the system.
-$\left\{ \begin{aligned}
2 x + y - \frac { 3 } { 2 } z & = - 3 \
\frac { 3 } { 2 } x - 3 z & = 0 \
x - 3 y & = - 10
\end{aligned} \right.$

Accepted Answer

A)  $( - 1,3 , - 2 )$ 
B)  $( - 1,11 , - 4 )$ 
C)  $( 6,3,1 )$ 
D)  $( - 4,2 , - 2 )$ 
A)  $( - 1,3 , - 2 )$ 
B)  $( - 1,11 , - 4 )$ 
C)  $( 6,3,1 )$ 
D)  $( - 4,2 , - 2 )$

Question 4

Solve the system of equations by the addition method.
-$\left\{ \begin{array} { l } 
\frac { x } { 4 } + \frac { y } { 4 } = 0 \
\frac { x } { 4 } - \frac { y } { 4 } = - 1
\end{array} \right.$

Accepted Answer

A)  no solution 
B)  infinite number of solutions 
C)  $( 2 , - 2 )$ 
D)  $( - 2,2 )$ 
A)  no solution 
B)  infinite number of solutions 
C)  $( 2 , - 2 )$ 
D)  $( - 2,2 )$

Question 5

Solve the system of equations by graphing.
-$\left\{ \begin{array} { l } 
y = - x - 1 \
y = 2 x + 8
\end{array} \right.$

Accepted Answer

A)  (-3, -2) 
B)  no solution 
C)  (-3, 2) 
D)  (-2, -3) 
A)  (-3, -2) 
B)  no solution 
C)  (-3, 2) 
D)  (-2, -3)

Question 6

Solve.
-Jamil always throws loose change into a pencil holder on his desk and takes it out every two weeks. This time it is all nickels and dimes. There are 7 times as many dimes as nickels, and the value of the dimes is $\$ 7.80$ more than the value of the nickels. How many nickels and dimes does Jamil have?

Accepted Answer

A)  12 nickels and 84 dimes 
B)  84 nickels and 12 dimes 
C)  11 nickels and 77 dimes 
D)  13 nickels and 91 dimes 
A)  12 nickels and 84 dimes 
B)  84 nickels and 12 dimes 
C)  11 nickels and 77 dimes 
D)  13 nickels and 91 dimes

Given the cost function, C(x), and the revenue function, R(x), find the number of units x that must be sold to break even. - C(x)=2000x+66,000 R(x)=8000x

Solve the system of equations by the substitution method. - $\left\{ \begin{array} { l } x + 8 y = - 7 \\- 7 x + 7 y = - 77\end{array} \right.$

Solve the system. - $\left\{ \begin{aligned}2 x + y - \frac { 3 } { 2 } z & = - 3 \\\frac { 3 } { 2 } x - 3 z & = 0 \\x - 3 y & = - 10\end{aligned} \right.$

Solve the system of equations by the addition method. - $\left\{ \begin{array} { l } \frac { x } { 4 } + \frac { y } { 4 } = 0 \\\frac { x } { 4 } - \frac { y } { 4 } = - 1\end{array} \right.$

Solve the system of equations by graphing. - $\left\{ \begin{array} { l } y = - x - 1 \\y = 2 x + 8\end{array} \right.$ $Solve the system of equations by graphing. - \left\{ \begin{array} { l } y = - x - 1 \\ y = 2 x + 8 \end{array} \right.$

Review of Real Numbers

Equations, Inequalities, and Problem Solving

Graphing

Exponents and Polynomials

Factoring Polynomials

Rational Expressions

More on Functions and Graphs

Inequalities and Absolute Value

Rational Exponents, Radicals, and Complex Numbers

Quadratic Equations and Functions

Exponential and Logarithmic Functions

Conic Sections

Sequences, Series, and the Binomial Theorem

Filters

Exam 4: Solving Systems of Linear Equations