NJSLA Mathematical Reasoning and Modeling 3

Question 1

Which situation can best be modeled by a linear function?

Accepted Answer

The distance traveled by a car moving at a constant speed

Answer

Constant speed means equal distance is covered each hour, producing a linear relationship between time and distance.

Question 2

The table shows: x = 1,2,3,4 and y = 5,8,11,14. What is the equation of the linear function?

Accepted Answer

y = 3x + 2

Answer

The rate of change is (8−5)/(2−1) = 3, and using the point (1,5): 5 = 3(1) + b gives b = 2, so y = 3x + 2.

Question 3

A scale model of a building uses a ratio of 1:200. If the model is 15 cm tall, how tall is the actual building in meters?

Accepted Answer

30 m

Answer

15 cm × 200 = 3,000 cm = 30 meters.

Question 4

A quadratic equation has roots at x = −3 and x = 5. Which equation represents this?

Accepted Answer

(x + 3)(x − 5) = 0

Answer

Roots at x = −3 and x = 5 come from factors (x + 3) = 0 and (x − 5) = 0.

Question 5

Maria earns $15 per hour and works h hours. Her rent is $900 per month. Which inequality models how many hours she must work to afford rent?

Accepted Answer

15h ≥ 900

Answer

She needs her earnings (15h) to be at least $900, so 15h ≥ 900.

NJSLA Exam Practice Test