3 2 - x is correct. Since 32 is the total games played, and x is her number of wins, the losses must be 32 take away x.

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1 Coordinate Algebra (CCGPS) EOCT Quiz Answer Key Algebra - (MCC9 12.A.SSE.1 ) Interpret Expressions, (MCC9 12.A.SSE.1b) Complicated Expressions, (MCC9 12.A.CED.1 ) Create Equations, (MCC9 12.A.CED.2) Graph Equations, (MCC9 12.A.CED.3) Represent Constraints, (MCC9 12.A.CED.4 ) Rearrange Formulas, (MCC9 12.A.REI.1 ) Explain Steps, (MCC9 12.A.REI.3 ) Linear Equations, (MCC9 12.A.REI.5 ) System Of Equations, (MCC9 12.A.REI.10 ) Understand Graph, (MCC9 12.A.REI.12 ) Graph Solutions Number and Quantity - (MCC9 12.N.Q.1 ) Use Units, (MCC9 12.N.Q.2 ) Descriptive Modeling, (MCC9 12.N.Q.3 ) Level Of Accuracy Student Name: Teacher Name: Micah Shue Date: Score: 1 ) Rick rents a car from a company that charges him $25 per day plus 10 cents per mile driven. Which expression can represent the amount he owed on a recent rental? A) 2 5 x + 0.1y B) 25.1x C) 25.1xy D) y 2 5 x + 0.1y is correct, where x is the number of days and y is the number of miles driven. 2 ) Selena played 32 games of chess. If she won x games, which expression represents her losses? A) 32x B) 32 + x C) x D) 32 x x is correct. Since 32 is the total games played, and x is her number of wins, the losses must be 32 take away x. 3 ) Simplify 3 - (4x - 5) + 6. A) 12x + 21 B) 4x + 14 C) 4x + 4 D) -4 x Get rid of parentheses first: 3-4x Combine like terms. The correct answer is -4 x ) The cost of tuition at Johnson Community College is $160 per credit hour. Each student also has to pay $50 in fees. Model the cost, C, for x credit hours taken. A) C(x) = 50x B) C(x) = 160x C) C(x) = 110x D) C(x) = x C(x) = x is correct, since the $50 cost is fixed, but the $160 cost increases as x increases. 1/15

2 5 ) Initially a pool contains 350 gallons of water. A hose is placed in the pool and the water is turned on. The hose adds 5.2 gallons of water per minute. Model the total amount, V, of water in the pool for x, the number of minutes the hose has been on. A) V(x) = 5.2x B) V(x) = 350x C) V(x) = 350x D) V(x) = 5.2x V(x) = 5.2x is correct, since the pool began with 350 gallons, and each minute, x, adds 5.2 gallons. 6 ) Find the rate of change for the ramp represented in the graph. Answer: 1/3 The solution is 1 3. The ramp is 5 inches high when it is 15 feet long. Change in height Change in length = 5 15 or /15

3 7 ) x y Which function corresponds with the table? A) f(x) = x + 2 B) f(x) = 2 x - 2 C) f(x) = -2x + 2 D) f(x) = -2x - 1 The function that corresponds with the table is f(x) = 2 x - 2. We can use the slope formula to find the slope (2 ). After finding the slope we can use any point to form an equation of the line using slope-intercept form. 8 ) Identify the equation of the graph shown. A) y = 2x + 3 B) y = 2x - 3 C) y = -2 x + 3 D) y = -2x - 3 The direction of the graph is decreasing, so the slope is negative. The y-intercept is at (0,3). Therefore, the equation of the graph is y = -2 x /15

4 9 ) Write an equation to model this situation. A) S = 4 A B) A = 4S C) S = 4 + A D) A = 4 + S Sam is 4 times as old as Allie can be written as S = 4 A. Sam is 4 times as old as Allie. 1 0 ) A concession stand sells hamburgers (h) for $2 and hotdogs (d) for $1. On Friday night they sold a total of 300 hamburgers and hotdogs and made $420. How many of each did they sell? Which system of equations matches the situation? A) B) C) D) The solution is A. Since there are a total of 300 hamburgers and hotdogs sold, we can set up one equation as h + d = 300. The other equation reflects the cost: 2h + d = ) Given 2x - y = 6, solve for y. A) y = 2x + 6 B) y = 2 x - 6 C) y = -2x + 6 D) y = -2x - 6 The correct answer is y = 2 x - 6. The steps for isolating y are shown. 2x - y = 6 2x = y + 6 y = 2x ) Given A = bh solve for b. A) b = Ah B) b = h A C) b = A h D) h = A b 4/15

5 The correct answer is b = A h. To solve for b you divide by h on both sides to get b = A h. 5/15

6 1 3 ) Solve. A) -5 B) -3 C) 7 D) 13 x = 2 Multiply both sides by 5. Subtract 3 from both sides. The answer is ) Solve. A) x = 1 B) x = 5 C) x = -7 D) x = -9 3(x + 1) - 2x = -6. The solution is x = -9. First using the D istributiv e P roperty, multiply the 3 into the parenthesis. Now combine any like terms on the left side of the equation. Using the Additiv e In v erse P roperty, subtract 3 from both sides. 1 5 ) Solve the system of equations. A) x = 1, y = 2 B) x = 2, y = 1 C) x = 1, y = 1 D) x = 0, y = 2 x + 3y = 5 -x + 6y = 4 The solution is x = 2, y = 1. You can solve the system by eliminating one of the variables. x + 3y = 5 -x + 6y = y = 9 y = 1 Then substitute 1 into one of the equations. x + 3(1) = 5 x = 2 6/15

7 1 6 ) Use the graph method to solve the system of linear equations: y - x = -2 an d 2 x + y = 7 A) (0,7) B) (2,0) C) (3.5,0) D) (3,1 ) (3,1 ) is correct. To graph the equations they need to be in slope-intercept form, or y = mx + b. By plotting the points we see that the system of equations intersect at (3,1). Thus, the solution is (3,1). 1 7 ) Which graph models the equation -2x + y = 4? A) 7/15

8 B) C) 8/15

9 D) The solution is Graph B. In this form, it is easier to see that when x = 0, y = 4, and when y = 0, x = -2. The line passes through (0, 4) and (-2, 0) 1 8 ) Graph y = 2x + 3 A) 9/15

10 B) C) 10/15

11 D) The sl ope is 2 or 2 1 an d th e y -in tercept is 3. So we start at 3 on th e y -axis an d th en go up 2 an d to th e righ t 1. The correct an swer is graph B. 11/15

12 1 9 ) The l in ear in equal ity y < - 2 x + 2 is graph ed. Determin e a sol ution for th e in equal ity. 3 A) (0, 2 ) B) (3, 0 ) C) (0, 0 ) D) (0, 3 ) The sol ution is (0, 0 ). Because th e l in e is dotted, th e poin ts th at l ie on th e l in e are n ot in cl uded. On l y poin ts in th e sh aded region are sol ution s for th e in equal ity. The poin t (0, 0 ) l ies in th e sh aded region. 12/15

13 2 0 ) Determin e a sol ution for th e l in ear in equal ity graph ed h ere. A) (3, 0 ) B) (3, -1 ) C) (0, 0 ) D) (5, 2 ) The sol ution is (0, 0 ). The poin t (0, 0 ) fal l s in th e y el l ow, sh aded region of th e in equal ity. 2 1 ) Ch an ge 2 7 cen timeters to mil l imeters. A) 2.7 mm B) 2 7 mm C) mm D) mm The sol ution is mm. There are 1 0 mil l imeters in 1 cen timeter. The sol ution is foun d by mul tipl y in g 2 7 by ) Mrs. Reed is decoratin g wreath s. Sh e n eeds 2 4 in. of gol d ribbon an d 4 5 in. of wh ite ribbon to tie aroun d each wreath. The wh ite ribbon is sol d by th e foot. About h ow man y feet of wh ite ribbon wil l Mrs. Reed n eed to make 1 8 wreath s? A) 3 0 ft B) 5 0 ft C) 7 0 ft. D) 9 0 ft. On e wreath n eeds 4 5 in. of wh ite ribbon. 1 8 wreath s 4 5 in /wreath = in. So Mrs. Reed wil l n eed about 7 0 ft of wh ite ribbon. 13/15

14 2 3 ) A studen t scored an 8 8, 9 2, an d 7 6 on th ree math tests. Wh at does th e studen t n eed to get on th e fourth test to h ave an average of 8 5 for al l four tests? James wan ts to use al gebra to sol ve th is probl em. Wh ich equation sh oul d h e use? A) 4 x = B) C) D) x x = 8 5 = = 8 5 x 4 To sol ve th is probl em, James sh oul d use x = 8 5. This is th e th ree kn own tests + th e fourth un kn own test 4 divided by th e total. This sh oul d equal 8 5, th e desired average. 2 4 ) Sarah an d Kel vin are cal cul atin g th e area of a circl e with a radius of 5 2 cm. Kel vin uses 3.14 for pi wh en cal cul atin g th is area wh il e Sarah uses th e pi button on h er cal cul ator. Kel vin gets a sol ution of 8, cm 2, an d Sarah gets a sol ution of 8, cm 2. Wh o h as th e most accurate sol ution? Wh y? A) Both an swers are equal l y accurate. B) Kel vin ; He did n ot h ave to roun d h is an swer. C) Neith er an swer is accurate as pi or 3.14 is n ot in th e formul a for th e area of a circl e. D) Sarah ; The pi button on th e cal cul ator gives a more accurate represen tation for pi th an The sol ution is Sarah ; The pi button on th e cal cul ator gives a more accurate represen tation for pi th an Usin g 3.14 as an approximation for pi y iel ds a l ess accurate resul t. 2 5 ) Wh ich is th e MOST precise measuremen t th is rul er can give for th e green strip of paper? A) 4.25 in ch es B) 4.50 in ch es C) 4.75 in ch es D) 5.00 in ch es 5.00 in ch es is correct. The scal e of th e rul er on l y al l ows for h al f-in ch precision, an d th e cl osest mark is at 5 in ch es. 14/15

15 2 6 ) Wh ich woul d give th e most precise measuremen t? A) Fin d th e distan ce between 2 cities to th e n earest mil e. B) Fin d th e distan ce between 2 cities to th e n earest 5 mil es. C) Fin d th e distan ce between 2 cities to th e n earest 1 0 mil es. D) Fin d th e distan ce between 2 cities to th e n earest mil es. The sol ution is Fin d th e distan ce between 2 cities to th e n earest mil e. Fin din g th e distan ce to th e n earest mil e, th ough difficul t, is th e most precise. 15/15