Intermediate Algebra (11th edition)

55.Concept Check Which sum could be simplified without first simplifying the individual
radical expressions?
A. B. C. D.

56.Concept Check Let and let

(a)Evaluate Then find Are they equal?

(b)Evaluate Then find Are they equal?

(c)Complete the following: In general, ,

based on the observations in parts (a) and (b) of this exercise.

57.Even though the root indexes of the terms are not equal, the sum
can be simplified quite easily. What is this sum? Why can we add these terms so easily?

58.Explain why is not equal to (This is a common error among algebra
students.)

Solve each problem.

59.A rectangular yard has a length of m and a width of m. Choose the best esti-
mate of its dimensions. Then estimate the perimeter.
A.14 m by 7 m B.5 m by 7 m C.14 m by 8 m D. 15 m by 8 m

60.If the sides of a triangle are in., in., and in., which one of the following
is the best estimate of its perimeter?
A.20 in. B.26 in. C.19 in. D.24 in.

Solve each problem. Give answers as simplified radical expressions.

61.Find the perimeter of the triangle. 62.Find the perimeter of the rectangle.

63.What is the perimeter of the computer 64.Find the area of the trapezoid.
graphic?

265 235 226

2192 248

28 - 422 2422.

264 + 23125 + 2416

2 na+ 2 nbZ

23 a+ 23 b. 23 a+b.

2 a+ 2 b. 2 a+b.

a= 1 b=64.

250 + 232 326 + 926 2332 + 23108 256 + 25192

SECTION 8.4 Adding and Subtracting Radical Expressions 457

3 √20 in. 2 √45 in.

√75 in.

√48 m

√192 m

4 √18 in.

3 √12 in.

2 √72 in.

√108 in.

√24 in.

√72 in.

√288 in.

Find each product. See Section 5.4.

Write in lowest terms. See Section 5.5.

15 y^3 - 9 y^2

6 y

8 x^2 - 10 x

6 x^2

12 p- 722 14 x^3 + 323 12 + 3 y 212 - 3 y 2

5 xy 12 x^2 y^3 - 4 x 2 13 x+ 7212 x- 62 1 a^2 +b 21 a^2 - b 2

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