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Mid-Chapter Quiz: Lessons 6-1 through 6-4
Use the graph to determine whether each
system is consistent or inconsistent and if it is
independent or dependent.
SOLUTION: The lines y = −2x + 3 and y = −2x − 3 never intersect
which means this system has no solution. So, the
system is inconsistent.
Graph each system and determine the number
of solutions that it has. If it has one solution,
name it.
4. x + y = 6
x −y = 4
SOLUTION: To graph the system, write both equations in slopeintercept form.
y = –x + 6
y=x–4
2. y = −2x + 3
y = −2x − 3
SOLUTION: The lines y = −2x + 3 and y = −2x − 3 never intersect
which means this system has no solution. So, the
system is inconsistent.
Graph each system and determine the number
of solutions that it has. If it has one solution,
name it.
4. x + y = 6
x −y = 4
SOLUTION: To graph the system, write both equations in slopeintercept form.
y = –x + 6
y=x–4
The graphs appear to intersect at the point (5, 1).
You can check this by substituting 5 for x and 1 for
y.
The solution is (5, 1).
6. x − 4y = −6
y = −1
SOLUTION: To graph the system, write both equations in slopeintercept form.
The graphs appear to intersect at the point (5, 1).
You can check this by substituting 5 for x and 1 for
y.
Graph
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The solution is (5, 1).
and y = –1.
Page 1
Mid-Chapter
Quiz:
6-1 through 6-4
The solution
is (5,Lessons
1).
6. x − 4y = −6
y = −1
The solution is (–10, –1).
8. 2x + y = −4
5x + 3y = −6
SOLUTION: To graph the system, write both equations in slopeintercept form.
SOLUTION: To graph the system, write both equations in slopeintercept form.
Equation 1:
Equation 2:
Graph
and y = –1.
Graph y = –2x − 4 and
The graphs appear to intersect at the point (–10, –1).
You can check this by substituting –10 for x and –1
for y.
The solution is (–10, –1).
.
The graphs appear to intersect at the point (–6, 8).
You can check this by substituting –6 for x and 8 for
y.
8. 2x + y = −4
5x + 3y = −6
SOLUTION: To graph the system, write both equations in slopeintercept form.
Equation 1:
Equation 2:
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The solution is (–6, 8).
Use substitution to solve each system of
equations.
10. y = −2x − 3
x +y = 9
SOLUTION: y = −2x − 3
x +y = 9
Page 2
Mid-Chapter Quiz: Lessons 6-1 through 6-4
The solution is (–6, 8).
Use substitution to solve each system of
equations.
10. y = −2x − 3
x +y = 9
SOLUTION: y = −2x − 3
x +y = 9
Substitute −2x − 3 for y in the second equation.
The solution is (–12, 21).
12. y = −4x
6x − y = 30
SOLUTION: y = −4x
6x − y = 30
Substitute −4x for y in the second equation.
Use the solution for x and either equation to find the
value for y.
Use the solution for x and either equation to find the
value for y.
The solution is (3, –12).
14. AMUSEMENT PARKS The cost of two groups
going to an amusement park is shown in the table.
The solution is (–12, 21).
12. y = −4x
6x − y = 30
SOLUTION: y = −4x
6x − y = 30
Substitute −4x for y in the second equation.
a. Define variables to represent the cost of an adult
ticket and the cost of a child ticket.
b. Write a system of equations to find the cost of an
adult and child admission.
c. Solve the system of equations, and explain what
the solution means.
Use the solution for x and either equation to find the
value for y.
d. How much will a group of 3 adults and 5 children be charged for admission?
SOLUTION: a. Let a = cost of an adult ticket and c = the cost of
a child ticket.
The solution is (3, –12).
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14. AMUSEMENT PARKS The cost of two groups
going to an amusement park is shown in the table.
b. The cost of a group with 4 adults and 2 children is
$184. So, 4a + 2c = 184. The cost of a group with 4
adults and 3 children is $200. So, 4a + 3c = 200. Page 3
a. Let a = cost of an adult ticket and c = the cost of
a child ticket.
Mid-Chapter Quiz: Lessons 6-1 through 6-4
b. The cost of a group with 4 adults and 2 children is
$184. So, 4a + 2c = 184. The cost of a group with 4
adults and 3 children is $200. So, 4a + 3c = 200.
Notice that the coefficients of the a terms are the
same, so subtract the equations.
Use the solution for c in either equation to find the
value of a.
The cost of an adult’s ticket is $38, and the cost of a
child’s ticket is $16.
the total cost of admission.
A group of 3 adults and 5 children visiting the
amusement park will be charged $194 for admission.
Use elimination to solve each system of
equations.
16. x + y = 9
x − y = −3
SOLUTION: Because y and −y have opposite coefficients, add the
equations.
Now, substitute 3 for x in either equation to find the
value of y.
The solution is (3, 6).
d. Substitute these values into the equation to find
the total cost of admission.
A group of 3 adults and 5 children visiting the
amusement park will be charged $194 for admission.
Use elimination to solve each system of
equations.
16. x + y = 9
x − y = −3
18. 9x − 24y = −6
3x + 4y = 10
SOLUTION: Multiply each term in the second equation by −3 to
eliminate the x coefficient.
Because 9x and −9x have opposite coefficients, add
the equations.
SOLUTION: Because y and −y have opposite coefficients, add the
equations.
Now, substitute 1 for y in either equation to find the
value of y.
Now, substitute 3 for x in either equation to find the
value of y.
The solution is (3, 6).
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18. 9x − 24y = −6
3x + 4y = 10
The solution is (2, 1).
Page 4
20. MULTIPLE CHOICE The Blue Mountain High
School Drama Club is selling tickets to their spring
musical. Adult tickets are $4 and student tickets are
Mid-Chapter
Quiz: Lessons 6-1 through 6-4
The solution is (2, 1).
20. MULTIPLE CHOICE The Blue Mountain High
School Drama Club is selling tickets to their spring
musical. Adult tickets are $4 and student tickets are
$1. A total of 285 tickets are sold for $765. How
many of each type of ticket are sold?
F 145 adult, 140 student
G 120 adult, 165 student
H 180 adult, 105 student
J 160 adult, 125 student
SOLUTION: Let a = the number of adult tickets sold and s = the
number of student tickets sold. So, a + s = 285 and
4a + 1s = 765.
Solve the first equation for s.
Substitute 285 – a for s in the second equation.
Use the solution for a in either equation to find the
value of s.
160 adult tickets and 125 student tickets were sold. So, J is the correct choice.
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Page 5