Keystone Test Algebra: Functions and Data 4

Question 1

The line of best fit for a data set is y = 1.5x + 2. Predict y when x = 10.

Accepted Answer

17

Answer

y = 1.5(10) + 2 = 15 + 2 = 17.

Question 2

Which value is NOT in the range of f(x) = x² for all real numbers x?

Accepted Answer

-1

Answer

x² is always non-negative, so -1 cannot be an output of f(x) = x².

Question 3

A box plot shows a minimum of 10, Q1 of 20, median of 30, Q3 of 45, and maximum of 60. What is the interquartile range (IQR)?

Accepted Answer

25

Answer

IQR = Q3 - Q1 = 45 - 20 = 25.

Question 4

Two functions: f(x) = 2x + 1 and g(x) = -x + 7. At what x-value do they intersect?

Accepted Answer

x = 2

Answer

Set 2x + 1 = -x + 7: 3x = 6, so x = 2.

Question 5

If the graph of f(x) is shifted up 3 units, which new function results?

Accepted Answer

f(x) + 3

Answer

Adding a constant k outside the function, f(x) + k, shifts the graph up by k units.

Keystone Test Practice Test