Download Chapter 2 Exam - Fall 2005 - SOLUTIONS

Ivy Tech Community College
MAT 050 Internet
Exam 2
SOLUTIONS
1. Evaluate: -3(x2 - 2y) when x = - 2 and y = 3.
= -3[(-2)2 - 2(3)] = -3(4 - 6) = -3(-2) = 6
2. Evaluate: - 4(a - 2b) - bc when a = 3, b = -2 and c = 4.
= - 4[3 - 2(-2)] -(-2)(4) = -4(3 + 4) -(-8) = -4(7) + 8 = -28 + 8 = -20
3. Simplify: 4p - 9p + 13p = 8p
4. Simplify: 5x + (-2x) + 9y = 3x + 9y
5. Simplify: 5x - 7y - 9x = - 4x - 7y
6. Simplify: 2a - 6b - ( - 11a) + 17b = 2a - 6b + 11a + 17b = 13a + 11b
7. Simplify: 1/5 (25x) = 5x
8. Simplify: (- 45x) (1/5) = -9x
9. Simplify: (3/2) (- 8x) = 3(-4x) = -12x
10. Simplify: (-2x) (-6) = 12x
11. Simplify: - 4(3x - 6) = -12x + 24
12. Simplify: 2(5x -2) = 10x - 4
13. Simplify: -2(3x2 - 4y2) = -6x2 + 8y2
14. Simplify: 5(3x2 - 4x - 1) = 15x2 - 20x - 5
15. Simplify: 3x - (5x + 4) = 3x - 5x - 4 = -2x - 4
16. Simplify: 3(2x - 4) - 4(3x-2) = 6x - 12 - 12x + 8 = -6x - 4
17. Simplify: - 6[2x - 3(x + 4)] = -6[2x - 3x - 12] = -6[-x - 12] = 6x + 72
18. Simplify: - 6x + 4[x - 6(2 -x)] = -6x + 4[x - 12 + 6x] = -6x + 4[7x - 12]
= -6x + 28x - 48 = 22x - 48
19. Translate “y decreased by the product of y and 2” into a variable expression.
y - 2y
20. Translate “the product of seven and the total of x and three” into a variable
expression.
7(x + 3)
21. Translate “three times the difference between a number and two” into a variable
expression.
3(x - 2)
22. Translate “a number multiplied by the sum of twice the number and one” into a
variable expression. x(2x + 1)
23. Translate and simplify “three less than the sum of a number and twelve.”
x + 12 - 3 = x + 9
24. Translate and simplify “nine more than the sum of two consecutive integers.”
n + n+1 + 9 = 2n + 10
25. A board 8ft long was cut into two pieces. Express the length of the shorter piece in
terms of the length of the longer piece, L.
8-L