Page 438 - Algebra 1

*21. Statistics The standard deviation is the square root of the variance of a set of data. (61) If the variance of a set of data is 24, what is the standard deviation in simplest
form?
22. Justify There are two different ways to write √ _75 in simplest form. Find both and (61) 45
then explain why each is correct.
*23. Error Analysis Two students solved the following systems of equations. Which
(63) student is correct? Explain the error.
Student A
2x + 11y = 13 2x + 9y = 11 20y = 24
y = 1.2 (–0.1, 1.2)
Student B
2x+11y =13 2x+6y =8 5y = 5 y=1
(1, 1)
24. Geometry The areas of two similar rectangles add up to 39 square (63) units. Twice the area of Rectangle A plus one-third the area
of Rectangle B equals 33 square units. What are the areas of Rectangles A and B?
25. Graph 9x - 1.5y + 12 = 0 using slope-intercept form. (49)
26. Solve the following system of linear equations: -3x + 2y = -6. (63)
-5x - 2y = 22
27. Multi-Step Use the system of linear equations to answer the problems below.
A
B
(55)
28. Boyle’sLaw Inchemistry,Boyle’sLawstatesthatthevolumeofasampleofgasis
(64) inversely related to its pressure if the temperature remains constant. Jameka recorded
the pressure of a sample of gas inside a 450-cubic millimeter container to be 95 kPa. If the pressure increased to 475 kPa, what would the new volume of the gas be?
29. Write Describe a proportional situation that is represented by the equation y = 6x. (56)
30. Generalize How would you describe the location of a graphed inverse variation (64) based on the constant?
a. Graph the system.
b. Determine the solution.
c. Check your answer by using substitution.
2x - y = 14 x + 4y = -2
Lesson 64 423