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Simplify each product using the FOIL method.
- (a + 8)(a - 2) 21. (x + 4)(4x - 5)
- (b - 3)(fc - 9) 24. (5m - 2)(m + 3)
- (3h + 2)(6h - 5) 27. (4w + 13)(m + 2)
- Geometry W hat is th e total surface area of th e cylinder?
W rite your answ er as a polynom ial in stan d ard form. - Design Ih e radius of a cylindrical gift box is (2x + 3) in.
The height of the gift box is twice th e radius. W hat is
th e surface area of th e cylinder? W rite your answ er as a
polynom ial in stan d ard form.
^ See Problem 3.
- 0 - 6 ) ( f c + 8 )
- (9z + 4)(5z - 3)
- (8c - l)(6 c - 7)
x 1 2 ^ See Problem 4.
x+ 5
1
Simplify each product.
- (x + 5)(x2 - 3 x + 1)
- (2a2 + 4a + 5)(5a - 4)
See Problem 5.
- O 2 — 4fc + 3 ) 0 — 2)
- (2g+7)(3g2 ~ 5 g + 2 )
- Sports A school’s rectangular athletic fields currently have a length of 125 yd an d
a w idth of 75 yd. The school plans to expand b o th th e length an d th e w idth of the
fields by x yards. W hat polynom ial in stan d ard form rep resen ts th e area of th e
expanded athletic field?
Simplify each product. Write in standard form.
- (x2 + l)(x - 3) 37. {-n2 — 1)(« + 3)
39. (2m2 + l)(m + 5) 40. (c2 - 4)(2c + 3) - Error Analysis D escribe an d correct th e error m ad e in
finding th e product. - Reasoning Is th e p ro d u ct of two polynom ials always a
polynomial? Explain.
(X -
- {b2 - 1 \b 2 + 3)
- (4z2 + l)(z + 3z2)
-= i(3 x U -
- Think About a Plan You are p lan n in g a rectangular dining pavilion. Its length
is three tim es its w idth x. You w an t a stone walkway th a t is 3 ft wide a ro u n d th e
pavilion. You have enough stones to cover 396 ft2 an d w an t to use th em all in the
walkway. W hat should th e dim ensions of th e pavilion be?- Can you draw a diagram th a t represents this situation?
- How can you write a variable expression for th e area of th e walkway?
- a. Simplify each p air of products.
i. (x + l)(x + 1) ii. (x + l)(x + 2) iii. (x + l)(x + 3)
11 - 1 1 11 • 12 11 • 13
b. Reasoning W hat are th e sim ilarities betw een your two answ ers in each pair
of products? - Geometry The dim ensions of a rectangular prism are n, n + 7, an d n + 8. Use the
formula V = (w h to write a polynom ial in standard form for th e volum e of the prism.
502 Chapter 8 Po l y n o m i al s an d Fact o r i n g