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Math 110, 111 Practice Quiz # 3 – Sections 2.1-2.4
Algebraic Expressions and Formulas, Simplifying
Expressions, Coordinate Plane, Graph of an Expression
1. Evaluate the expression. Simplify to lowest terms when necessary. Round answers to the
nearest hundredth if necessary.
y  y1
a. 2
; x1 = 3, x2 = -2, y1 = -4, y2 = -5
1/5
x2  x1
b. 2x 2  3x  5 for x = 3
c. –x2 + y; for x = -3, y = -5
d. –x2 + y; for x = 5, y = -2
14 or 3.74
-14
-27
2. The temperature in Thailand is 30o Celsius. To convert to Fahrenheit use the formula
F = 9/5 C + 32. What is the Fahrenheit temperature?
86o F
3. Simplify the expression.
a. 6x2 + 2x + 3 + 4x2 – 3x – 5
b. –(2a + 3) – (5a – 4)
10x2 – x – 2
-7a + 1
4. Translate the given information into an equation. Let x represent the unknown number and
then solve for x.
a. Decreasing a number by 20% results in 60.
b. A number is increased by 1/3 of the number and the result is 20.
c. The quotient of twice a number and 4 is 10.
n – .20n = 60; 75
n + 1/3n = 20; 15
2n/4 = 10;
20
5. Plot the points associated with the given ordered pairs.
a. A (2, 4), B (-3. 5), C (-2, -5)
b. A (1, -3), B (0, 5), C (-2, 0)
c. A (0, 0), B (4, -3), C (-2, -3)
d. A (5, 4), B (5, -4), C (-5, 4)
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6. Refer to the coordinate plane shown and determine the coordinates of the points.
a. A
(-2, 4)
b. B
(0, 2)
c. C
(-2, 1)
d. D
(-3, -2)
e. E
(0, -4)
f. F
(-3, 0)
7. Name the quadrant in which each point lies.
a. P ( -2, 5 )
Q II
b. Q ( 4, 1/5 )
QI
c. R ( - 3 , - 5 )
Q III
d. S ( x, y ), y < 0, x = 5
Q IV
8. On a grid map with coordinates in miles, your house is located at ( 4, 6 ). Your school is
located at ( -5, 2 ).
97or  9.8miles
a. How far is it from your house to your school?
b. What are the coordinates of the midway point from your house to your school? ( -1/2, 4 )
9. Evaluate the expression for the given values using your calculator. Fill in the table of x, y
values
a. y = 2x + 3
b. y = x2 – 4;
c. y = 7 – 4x
x
2x + 3
x
x2 – 4
x
7 – 4x
-1
1
-1
-3
-1
11
2
7
-4, 4
12
0
7
5
13
5
21
5
-13
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