2. Word Problems
¢Decide if the problem involves addition, subtraction or
multiplication.
¢If polynomials are given: add, subtract or multiply like
normal.
¢If polynomials are not given: use a formula.
—Area = length times width
—Perimeter = add all sides
4. From 1991 through 1998, the number of
commercial C and education E Internet
websites can be modeled by the following
equations, where t is the number of years
since 1991.
C = 0.321t^2 – 1.036t + 0.698
E = 0.099t^2 – 0.120t + 0.295
Find a model for the total number of
commercial and education sites.
tHE ANSWER :
6. From 1890 through 1990, the total number of people T and the number of men M in
the US labor force can be modeled by the following equations, where t is the number
of years since 1890.
¢
T = 0.0086t
2
+ 0.087t + 25.375
M = 0.0016t
2
+ 0.315t + 19.467
Find a model for the number of women in the US labor force.
8. Word Problem #3
A triangle has 3 sides with lengths 8x + 6, 5x – 5, and -6x +
12. What is the perimeter of the triangle?
7x + 13
8x + 6 + 5x - 5 + -6x + 12
7x + 13
9. Word Problem #4
The dimensions of
a window are 3x +
10 and 2x + 6.
What is the area
of the window?
ANSWER :
(3x+10)(2x+6) =
6x^2 + 38x + 60
12. Word Problem #7
The cost of a video game
can be modeled by the
equation C = 3x + 2. The
number of games sold can
be modeled by the equation
N = 8x – 7. Write a model
for the revenue from the
sale of the games.
R = 24x
2
– 5x – 14
Answer :
13. Word problems
The profit a business makes is found by
subtracting the cost to produce an item C
from the amount earned in sales S. The
cost to produce and the sales amount could
be modeled by the following equations, where
x is the number of items produced.
C = 100x
2
+ 500x – 300
S = 150x
2
+ 450x + 200
Find an equation that models the profit.
A. 50x2 – 50x + 500
B. –50x2 – 50x + 500
C. 250x2 + 950x + 500
D. 50x2 + 950x + 100
14. Word problems
Write an expression for
the area of the
rectangle.
A. 7x + 3 units^2
B. 12x2 + 11x + 2 units^2
C. 12x2 + 8x + 2 units^2
D. 7x2 + 11x + 3 units2