Problem 1 · Real Numbers and Algebraic Expressions · 9 points
Compare two discount offers
A jacket has price p>0. Store A takes 20% off, then subtracts 5 dollars. Store B subtracts 5 dollars, then takes 20% off. Ignore tax.
- A. Write and simplify both price expressions.
- B. Find the difference and evaluate both at p = 60.
- C. State the price range where both final prices are nonnegative and explain why order matters.
Show worked solution and rubric
- A. A: 0.8p−5. B: 0.8(p−5)=0.8p−4. Multiplication distributes over both terms in B.
- B. B costs 1 more for every allowed p. At p=60, A costs 43 dollars and B costs 44 dollars.
- C. A requires p≥6.25; B requires p≥5. Both are nonnegative for p≥6.25. Taking 20% off the five-dollar reduction saves only four dollars in B.
Scoring rubric
- 3 points: A: 0.8p−5
- 3 points: B costs 1 more for every allowed p
- 3 points: A requires p≥6.25; B requires p≥5
Review this unitProblem 2 · Linear Equations and Inequalities · 9 points
Plan an hourly rental
A bicycle rental costs 18 dollars plus 7 dollars per hour. The budget is at least 60 dollars and at most 95 dollars. Only whole hours may be rented.
- A. Form and solve a compound inequality.
- B. List all allowed whole-hour values.
- C. Explain what changes if the upper budget is strictly less than 95 dollars.
Show worked solution and rubric
- A. 60≤18+7h≤95 gives 42≤7h≤77, hence 6≤h≤11.
- B. The allowed values are 6,7,8,9,10,11 hours. Both endpoints satisfy the original budget.
- C. Then h<11, so the whole-hour values become 6,7,8,9,10. The value 11 costs exactly 95 dollars.
Scoring rubric
- 3 points: 60≤18+7h≤95 gives 42≤7h≤77, hence 6≤h≤11.
- 3 points: The allowed values are 6,7,8,9,10,11 hours
- 3 points: Then h<11, so the whole-hour values become 6,7,8,9,10
Review this unitProblem 3 · Linear Functions and Coordinate Geometry · 9 points
Build a line from measurements
A line passes through (−1,4) and (2,−2).
Problem diagram- A. Find the slope and equation.
- B. Find both intercepts and explain the sign of the slope.
- C. Write the equation of the perpendicular line through (2, -2).
Show worked solution and rubric
- A. m=2−(−1)−2−4=−2. Using y=mx+b gives b=2, so y=−2x+2.
- B. The intercepts are (0,2) and (1,0). Each increase of one in x lowers y by two.
- C. The perpendicular slope is 21, since (−2)(21)=−1. Thus y+2=21(x−2), or y=21x−3.
Solution diagramScoring rubric
- 3 points: m=2−(−1)−2−4=−2
- 3 points: The intercepts are (0,2) and (1,0)
- 3 points: The perpendicular slope is 21, since (−2)(21)=−1
Review this unitProblem 4 · Systems of Equations and Inequalities · 9 points
Sell tickets for a school event
A club sells 40 tickets. Adult tickets cost 12 dollars and student tickets cost 8 dollars. Revenue is 400 dollars.
- A. Define variables and write two equations.
- B. Solve the system and verify revenue.
- C. If capacity becomes at most 40 and revenue must be at least 400 dollars, state the inequalities, including domain restrictions.
Show worked solution and rubric
- A. Let a and s be adult and student tickets. Then a+s=40 and 12a+8s=400.
- B. Subtract 8(a+s)=320 from the revenue equation: 4a=80, so a=20,s=20. Revenue is 240+160=400.
- C. a+s≤40, 12a+8s≥400, with nonnegative integers a,s. A feasible ticket count must satisfy all constraints.
Scoring rubric
- 3 points: Let a and s be adult and student tickets
- 3 points: Subtract 8(a+s)=320 from the revenue equation: 4a=80, so a=20,s=20
- 3 points: a+s≤40, 12a+8s≥400, with nonnegative integers a,s
Review this unitProblem 5 · Polynomials and Factoring · 9 points
Find a rectangular garden
A garden has area x2+5x+6 square meters and one side x+2 meters, where x>0.
- A. Factor the area and find the other side.
- B. Write and simplify the perimeter.
- C. Find x when the area is 30 square meters; justify rejecting any root.
Show worked solution and rubric
- A. x2+5x+6=(x+2)(x+3), so the other side is x+3 meters.
- B. P=2(x+2)+2(x+3)=4x+10 meters.
- C. x2+5x−24=(x+8)(x−3)=0. The roots are −8,3; only x=3 fits x>0. The sides are 5 and 6 meters.
Scoring rubric
- 3 points: x2+5x+6=(x+2)(x+3), so the other side is x+3 meters.
- 3 points: P=2(x+2)+2(x+3)=4x+10 meters.
- 3 points: x2+5x−24=(x+8)(x−3)=0
Review this unitProblem 6 · Quadratic Equations and Models · 9 points
Analyze a thrown ball
A ball has height h(t)=−5t2+20t+1 meters for time t≥0 seconds, until it hits the ground.
Problem diagram- A. Complete the square and find the maximum height and time.
- B. Find the exact time the ball hits the ground.
- C. State the physical domain and when the ball is rising.
Show worked solution and rubric
- A. h(t)=−5(t−2)2+21, so the maximum is 21 meters at 2 seconds.
- B. 5t2−20t−1=0 gives t=2±5105. Only 2+5105 is nonnegative.
- C. The physical domain is 0≤t≤2+5105. The ball rises for 0≤t<2 and falls after the vertex.
Solution diagramScoring rubric
- 3 points: h(t)=−5(t−2)2+21, so the maximum is 21 meters at 2 seconds.
- 3 points: 5t2−20t−1=0 gives t=2±5105
- 3 points: The physical domain is 0≤t≤2+5105
Review this unit