Algebra 1 Midterm 2012-2013 Study Guide Name___________________________ Date:______________ Period:___________ THIS REVIEW WILL BE COLLECTED JANUARY 4th or January 7th . One problem each page will be graded! You may not turn this exam review in after the due date! Evaluate the expression for the given values of the variables. 1) 3n when n = 4 _____ 3) 2) 8 + 5a2 when a = 7 3a − 7 when a = -4 _____ 2 4) ____ n + m 2 when m = -2 and n = -3 ______ Evaluate. 5) _____ 8) _____ 9) 11) 12) 6) _____ ______ 7) 10) _____ ______ _____ Check whether the given number is a solution of the equation or inequality: ; 5 _____ Tell whether the pairing is a function. 13) _________ Input 1 2 3 4 14) __________ Output 20 21 21 22 Input 5 10 10 20 Output 10 15 20 25 15) Write the verbal sentence as an equation or an inequality: Five is less than a number x divided by 7. 16) Write an equation or inequality to model the situation: equal to four times the difference of a number n and 5. _______________ The perimeter P of a square is less than or _____________ 1 Simplify. 17) ______ 18) ____ 19) _____ 20) ______ Solve the equation. 21) _____ 24) _____ 27) 4x – 1 = 2(2x + 3) 22) ______ 25) 28) − _____ 2 ( 6 x − 9 ) = −4 x + 6 3 30) Identify the property being illustrated: -8 + 8 = 0 23) 26) _____ _____ 29) 4(2- 2y) + 6 = 2(7 = 4y) _____ __________________________ 31) Which statement illustrates the Commutative Property of Multiplication? A) 3i( 4 + 2 ) = 3i 4 + 3i2 C) 3i( 4i2 ) = ( 4i2 )i3 B) 3i( 4i2 ) = ( 3i 4 )i2 D) 3 + ( 4i2 ) = ( 4i2 ) + 3 32) Members of a local gym pay a yearly fee of $150 and $2 per day to use the volleyball courts. Write a function of the cost in terms of the number of days you use the volleyball courts. ____________________ 33) Rewrite the equation so that y is a function of x. ____________________ 2 34) Decide whether the given ordered pair is a solution of the equation. _______ 35) Find the x-intercept. _____ 36) Find the y-intercept. ______ 37) Find the slope of the line passing through the points. 38) Find the value of y so that the line passing through the two points has the given slope. ______ _____________ 39) Find the slope and the y-intercept of the graph 4x – 9y + 18 = 0. 40) _____________ In 1999, a software company had a profit of $30,000,000. In 2005, the company had a profit of $210,000,000. Find the average rate of change of the company's profit in dollars per year. ___________________________ 41) The variables x and y vary directly. Use the given values to write an equation that relates x and y. __________________ For questions 42 – 45: State whether the equation is a direct variation. If so, state the constant of variation. 42) y = 4 _____________ 43) 3x – 4y = 0 _____________________ 44) -x + 2y = 4 ________________ 45) 2 + 4y = -4x + 2 ______________________ 46) Each month, Laura’s cell phone charges c vary directly with the number of minutes m that she talks. Last month, she talked 450 minutes and was charged $13.50. a) Write a direct variation equation that relates c and m. _____________________ b) How much would Laura pay if she talked 300 minutes? _____________________ 3 Graph the equations. 47) 6 x − 4 y = 8y 48) x – y = 1 x 50) 51) 5(x + 1) = y –y 10 y 2 x +2 3 y x x 52) x = 1 y x x x 53) y = − 49) y = − y 2 x + 3 for the domain x > 3 3 54) x - 2y = 4 for the domain -4 ≤ x ≤ 4 y y 53) Range: _______________________ 54) Range: _______________________ x x 4 55) Decide whether the graphs of the two functions are parallel lines. _____________ 56) Write a rule for the function of the values in the table below? Input, x Output, y 57) 1 9 2 12 3 15 4 18 ____________________ 5 21 A music store sells CDs for $12.99 each. a. Write a rule for the cost of CDs as a function of the number of CDs purchased. _____________ b. Let the domain equal 0, 1, 2, and 3. Make a table and identify the range. ___________________ 58) Mrs. Fox loves basketball and was able to get the season NBA Pass for $140 per year and $3.50 for each game she watches on tv. Write the function that relates the variables. _________________ 59) Which equation is an identity? Which has no solutions? _____________________ ____________________ _____________________ 60) Write as a function of x. _____________________ ___________________ 61) State the x- and y-intercepts of the line with the equation y = -3x + 6. 62) Determine the slope of the line graphed below. 63) Find the slope of the line that contains (2, 4) and 64) Find the slope of the line through the points (–1, –3) and (–1, 7). ________ _______ _______________ ___________________ ____________________ 5 65) On January 1, Mario had a savings account balance of $2742 and by April 1, his balance had increased to $3597. Find Mario's average savings rate in dollars per month for that period. _________________________________ 66) Rewrite the equation in slope-intercept form. 67) Find the slope and y-intercept of the line with the equation 68) Determine if the line 69) In the equation y = 70) True or False: The graphs of direct variation equations always contain the point (0, 0). ________ 71) Let 72) What is the value of the function when 73) Find the value of x so that is parallel to the line _____________ . _________ _________ . _____________ , does y vary directly with x? ________ Find x when ____________ . ?. ___________ ________________ Write the equation of the line that passes through the points in slope-intercept form AND standard form. 74) (4, -3) and (2, -2 ) __________________ ________________ 75) (0, 5) and (-3, -1) __________________ ________________ 76) (5, 9) and (6, 4) __________________ ________________ 6 77) Write the equation of the line that passes through (7, -8) with a slope of -3. _________________ 78) Write the equation of the line that passes through the point (1, 7) and is parallel to the line -6x + y = -1. ____________________ 79) Write the equation of the line that passes through the point (-2, -4) and is perpendicular to the line 2 7 y = − x +1 ____________________ 80) For the given data set -2, 8, 12, -7, 10, 3 find: a. the mean ______ Round to 3 significant figures if necessary. b. the MAD score _____ c. the variance _____ d. standard deviation _____ 7 81) You scored an 82 on your statistics test. The mean for the class was 85 and the standard deviation was 3.4. a. Calculate your z-score. ___________ b. Mark where your z-score falls on a bell curve. c. Within how many deviations of the mean is your score? __________________ 82) You took a test and earned a z-score of 2.5. The mean for the test was 79 and the standard deviation was 6. What was your raw score? _______________________ 83) The following numbers represent the number of stories in the world’s 10 tallest buildings: 140, 88, 88, 108, 88, 88, 80, 69, 102 and 78. a) Find the mean:_______________ b) median: _______________ c) mode: _______________ d) Make a box-and-whisker plot of the data. Identify any outlier. 8