Page 518 - Algebra 1

12. Use mental math to find the product of 17 · 23. (60)
*13. City Parks The City Works Department wants to build a new fence around 8 - √4 feet (76) the town’s park. Write an expression for the area of the figure at right. Find
the area.
*14. Justify Explain how to find the product of √2 (√ 3 - √ 8). (76)
*15. Write Find two radical expressions that when multiplied together equal a (76) perfect square.
*16. Multiple Choice Which expression is not equivalent to √ 48?
(76) A √ 3· 1 6 B 16√ 3 C √ 42· 3 D 4√3
17. Vacation The cost of a vacation, in dollars, is represented by the expression
(9) 46x2 - 9x + 95, where x is the number of nights. What is the cost of a 3-night
vacation?
18. Error Analysis Two students factor 5x2 - 6x - 8. Which student is correct? Explain
(75) the error.
*19. Geometry The sum of the squares of the two legs of a right triangle is
(75) 16x2 - 40x + 25. Factor the expression, and then take the square root to find the
expression that represents the length of the hypotenuse.
20. Multi-Step The area of a rectangular ottoman is represented by 2x2 + 3x - 27 (75) square inches.
a. Evaluate the expression for x = 12. b. Factor the expression completely.
21. Error Analysis Two students are solving |3x| = 6. Which student is correct? Explain (74) the error.
8 - √4 feet
Student A
(5x + 4)(x - 2)
Student B
(5x - 4)(x + 2)
Student A
|3x| = 6
3x = 6
3x - 3 = 6 - 3
x = 3
The solution set of |3x| = 6 is {6, -6}.
3x = -6
3x - 3 = -6 - 3
x = -9
Student B
|3x| = 6
3x = 6 3x = -6
3 x = 6 _3 x = - 6 ___
3333 x = 2 x = -2
The solution set of ⎢3x = 6 is {2, -2}.
*22. HouseholdSecurity Awindowguardisdesignedtobeplaceddirectlyintowindows (74) that are 27 inches wide. The guard can be compressed or expanded with a tension
spring to fit windows that are three inches narrower or wider than the standard width. Write and solve an absolute-value equation for the maximum and minimum width of windows in which the guard is designed to fit.
Lesson 76 503