CHAPTER 6 Review Exercises^415
(a)Use the model to find the number of alternative-fueled vehicles in 2005, to the near-
est thousand. How does the result compare with the actual data in the table?
(b)Use the model to estimate the number of alternative-fueled vehicles in 2007, to the
nearest thousand.
(c)Why might the estimate for 2007 be unreliable?81.A pyramid has a rectangular base with
a length that is 2 m more than its
width. The height of the pyramid is 6 m,
and its volume is Find the
length and width of the base.82.A lot is in the shape of a right triangle.
The hypotenuse is 3 m longer than the
longer leg. The longer leg is 6 m
longer than twice the length of the
shorter leg. Find the lengths of the
sides of the lot.48 m^3.x
x + 26??xbhLW83.The triangular sail of a schooner has
an area of The height of the sail
is 4 m more than the base. Find the
base of the sail.84.The floor plan for a house is a rectangle
with length 7 m more than its width.
The area is Find the width and
length of the house.170 m^2.30 m^2.MIXED REVIEW EXERCISES
63.Concept Check Which of the following is notfactored completely?
A. B. C. D.
64.A student factored as. Explain why the polyno-
mial is not factored completely, and give the completely factored form.Factor completely.Solve.
- 80.The product of the first and second of three consecutive integers is equal to 23 plus
the third. Find the integers.
- 80.The product of the first and second of three consecutive integers is equal to 23 plus
t 1 t- 72 = 0 x^2 + 3 x= 10 25 x^2 + 20 x+ 4 = 049 t^2 + 56 t+ 16 1000 a^3 + 2712 r^2 + 18 rq- 10 r- 15 q 2 a^5 - 8 a^4 - 24 a^312 x^2 yz^3 + 12 xy^2 z- 30 x^3 y^2 z^425 a^2 + 15 ab+ 9 b^224 ab^3 c^2 - 56 a^2 bc^3 + 72 a^2 b^2 c 6 m^3 - 21 m^2 - 45 my^4 - 625 15 m^2 + 20 m- 12 mp- 16 p3 k^2 + 11 k+ 10 z^2 - 11 zx+ 10 x^26 x^2 + 16 x- 32 12 x+ 8213 x- 42317 t 2 3 x 17 t+ 42 13 +x 217 t+ 42 317 t+ 42 +x 17 t+ 42