Writing Equations
All 194 students in the Math Club went on a field trip. They took 8 vehicles - some students rode in vans which hold 7 students each and some students rode in buses which hold 30 students each.
v + b = 8
7v + 30b = 194
y = -6x
y = -5x + 4
Options: (-1,4) (-4,24) (-8,-4)
(-4, 24)
MUST use a table
g + m = 12
4.50g + 3.99m = 49.92
g = 4
m = 8
MUST graph on paper or calculator
y = 1x + 1
y = 4
(3, 4)
MUST use the substitution method
y = 9x − 9
y = 9
(2, 9)
Jennifer spent $38 on 6 shirts. Short sleeve shirts cost $6 and long sleeve shirts cost $7.
s + l = 6
6s + 7l = 38
y = 8x - 11
y = -3x
Options: (-1, 8) (-1, -3) (1, -3)
(1, -3)
MUST use a table
x + y = 100
.75x + 1.25y = 90
x = 70
y = 30
MUST graph on paper or calculator
y = 1x - 2
y = ((-1 / 4)x) + 3
(4, 2)
MUST use the substitution method
y = 7
6x + 4y = 10
(-3, 7)
Printing Inc. has two type of printing presses: Model A and Model B. In one week 12000 books are made. Model A can print 50 books per day and Model B can print 70 books per day. Altogether Printing Inc has 20 printing presses.
A + B = 20
50A + 70B = 12,000
5x − 5y = 5
y = 2x
Options: (6, 1) (6, -2) (-1, -2)
(-1, -2)
MUST use a table
Gabriella spent $245 on books. Math books cost $25 and English books cost $29. If she bought a total of 9, then how many of each kind did she buy?
4 Math books
5 English books
MUST graph on paper or calculator
y = -1x + 3
y = -1x + 1
MUST use the substitution method
y = -2x
y = -5x
(0, 0)
The admission fee at a small fair is $1.50 for children and $4.00 for adults. On a certain day, 2200 people enter the fair and $5050 is collected.
c + a = 2200
1.50c + 4a = 5050
y = 8x
7x − y = 1
Options: (4, −5) (−8, −1) (−1, −8)
(−1, −8)
MUST use a table
A school uses 8 vehicles to go on a trip. Each car holds 4 students and each van holds 8 students. If 52 students went on the trip, then how many of each type of vehicle did the school use?
3 cars
5 vans
MUST graph on paper or calculator
y = 1x - 5 + 1x
y = 4x - 5 - 2x
Infinite Solution
MUST use the substitution method
y = 8x
-24x + 3y = -2
No Solution
A farmhouse shelters 6 animals. Some are horses and some are geese. Altogether there are 20 legs.
h + g = 6
4h + 2g = 20
5x − 3y = −6
y = 2x
Options: (−6, 12) (6, 12) (−6, 5)
(6, 12)
MUST use a table
There are 15 animals in the field. Some are pigs and some are ducks. There are 42 legs in all. How many of each animal are in the field?
9 ducks
6 pigs
MUST graph on paper or calculator
y = ((-7 / 2) x) - 4
y = ((-1 / 2) x) + 2
(-2, 3)
MUST use the substitution method
y = 3x - 12
y = 20 - x
(8, 12)