Linear Functions Flashcards
8 cards from real Bluebook SAT Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 8 Linear Functions flashcards as text
Which of the following equations represents a linear function?
Answer: y = 3x + 2
y = 3x + 2 is the only equation of the form y = mx + b, making it linear.
The function R(x) = −2x + 14 models the remaining miles x days into a road trip. On what day will 4 miles remain?
Answer: 5
−2x + 14 = 4 → −2x = −10 → x = 5.
A linear function f has the equation f(x) = px − 8. If f(4) = 4, what is the value of p?
Answer: 3
4p − 8 = 4 → 4p = 12 → p = 3.
Line m passes through (2, 5) and is perpendicular to a line with slope −1/3. What is the equation of m?
Answer: y = 3x − 1
Perpendicular slope = 3; using (2, 5): 5 = 3(2) + b → b = −1; y = 3x − 1.
The points (1, a) and (4, 13) lie on a line with slope 2. What is the value of a?
Answer: 7
(13 − a)/(4 − 1) = 2 → 13 − a = 6 → a = 7.
A line passes through the origin and the point (5, −15). Which equation represents this line?
Answer: y = −3x
Slope = (−15 − 0)/(5 − 0) = −3; passes through origin means y-intercept = 0: y = −3x.
In the linear equation 4y − 3x = 8, what is the x-intercept?
Answer: (−8/3, 0)
Set y = 0: −3x = 8 → x = −8/3; x-intercept is (−8/3, 0).
f(x) = 6x − 4 and h is a linear function parallel to f with h(0) = 7. What is h(3)?
Answer: 25
Parallel to f means same slope 6; h(0) = 7 means y-intercept = 7; h(3) = 6(3) + 7 = 25.