AlgebraMediumFunction value from its two intercepts
Algebra practice question
The graph of a linear function f in the xy-plane has x-intercept 6 and y-intercept −3. What is the value of f(10)?
Answer: 2
Through (6, 0) and (0, −3): slope = (0 − (−3))/(6 − 0) = 1/2, so f(x) = (1/2)x − 3. Then f(10) = 5 − 3 = 2.
Common wrong answers
- If you answered 5
- 5 forgets the intercept −3.
- If you answered 17
- 17 uses slope 2, inverting rise and run.
- If you answered -8
- −8 uses slope −1/2.
More Algebra questions
- Medium
A system: 2x + y = 11 and x − y = 1. What is the value of x + y? - Medium
Which of the following describes all solutions to 4x − 9 ≤ 2x + 5? - Medium
A phone's battery percentage is modeled by P = 100 − 8t, where t is the number of hours since it was unplugged… - Medium
If y = 2x − 1 and 3x + y = 14, what is the value of x? - Medium
If |2x − 3| = 7, what is the sum of all possible values of x? - Medium
Line k has equation y = (2/3)x + 1. Which equation represents a line perpendicular to line k?
Not affiliated with the College Board. SAT is a trademark of the College Board.