Page 112 - Algebra 1

*21. Error Analysis Two students simplified an algebraic expression. Which student is
(15)
22. Probability There are 400 students in the cafeteria. Of these students, 120 are
(14)
23. Error Analysis Two students simplify the expression -7 - x + 7. Which student is
(12)
correct? Explain the error.
Student A
2r3t (r5t2 + 4r3t3) = 2r15t2 + 8r9t3
Student B
2r3t (r5t2 + 4r3t3) = 2r8t3 + 8r6t4
tenth-graders. What is the probability of randomly selecting a tenth-grader? Express the answer as a percent.
correct? Explain the error.
Student A
-7-x + 7
= x + (-7) + 7 = x + (-7 + 7) =x+0
=x
Student B
-7-x + 7
= -7 + 7- x = (-7 + 7)- x =0-x
= -x
3 4
24. Justify Simplify -_2 ÷ (-_8 ). Show your steps. (11) 39
25. Write Must the algebraic expression x + 7y have only one value? Explain. (9)
26. Measurement Madison used a scale and measured her weight at 85 pounds. How
(8)
27. Energy Conservation Wind turbines take the energy from the wind and convert it
_π 4
withdrew a total of $186.15. Use addition to find the net change in Tonia’s checking account.
29. Justify What is the first step in simplifying the expression 2 · 4 + 52 + (23 - 2)2 ? (4)
30. Payroll Accounting Employees at Wilkinson Glass Company earn x number of
(15) dollars per hour. Executives make y number of dollars per hour. Each employee
and executive works 40 hours per week. Write and simplify an algebraic expression that uses the Distributive Property to show a weekly payroll for one employee and one executive.
(5)
many kilograms does Madison weigh? (Hint: 1 kilogram = 2.2 pounds.)
(4) to electrical energy. Use the formula P = ad 2v3
28. Finance Tonia deposited a total of $174.52 into her checking account. She also
e to find the amount of available energy in the air. Describe the steps you would take to simplify the formula.
Lesson 17 97