Page 130 - Algebra 1

*11. Error Analysis Two students completed an x/y chart for the equation y = 3 + 2x to (20) find a solution to the equation. Which student is correct? Explain the error.
Student A
x
y
2
10
y = 3 + 2(2)
y = 5(2)
y = 10
(2, 10) is a solution.
Student B
x
y
2
7
y = 3 + 2(2) y=3+4
y=7
(2, 7) is a solution.
x
5
10
20
50
y
*12. Multi-Step For a lemonade stand, profit depends on (20) the number of cups sold. Profit is represented by the equation y = x - 5, where x is the number of
cups sold and y is the profit in dollars.
a. Complete the table and graph the solutions.
b. How would you find the profit if 30 cups were sold?
13. Geometry The triangle has a perimeter of 24 centimeters. Find the value for x.
*14. Multi-Step To climb to the highest observation deck in the Empire State Building, (19) you have to walk up 1860 steps. Starting at the lowest step, a security guard walks
up _1 the total number of steps during his morning rounds. At the end of his 4
afternoon rounds, he stands on the 310th step. How many steps did he walk down during the afternoon rounds?
*15. Error Analysis Two students simplify the expression 5x2 + 7x2. Which student is (18) correct? Explain the error.
16. Write Why do mathematicians use symbols rather than words? (17)
17. Multiple Choice Which equation demonstrates the Associative Property of (12) Addition?
(19) x
8 cm 10 cm
Student A
12x2
Student B
12x4
A 6-3c=3c-6 B c3 -6=c3 +6
C (6 - c)3 = (c - 6)3 D (6 + c3) - 4 = 6 + (c3 - 4)
18. Evaluate each of the following expressions when a = 2. (16) a. a2 b. -a2 c. -a3 d. (-a)3
e. |(-a)2|
19. Analyze A school is holding a blood drive. If 3 students out of the 50 who give (14) blood are Type A, what is the probability that a randomly selected student is
Type A? Write the probability as a decimal.
20. Evaluate √ 44 1 + √ 108 9. (13)
Lesson 20 115