16Hit1600
AlgebraHardLinear function from a table with negative slope

Algebra practice question

x: 2, 5, 8 g(x): 14, 8, 2

The table gives values of a linear function g. Which equation defines g?

  1. A. g(x) = −2x + 18Correct
  2. B. g(x) = 2x + 10
  3. C. g(x) = −2x + 14
  4. D. g(x) = −3x + 20

Answer: A. g(x) = −2x + 18

From x = 2 to x = 5, g falls by 6, so the slope is −2. Then 14 = −2(2) + b gives b = 18. Check x = 8: 2 ✓.

Why the other answers are wrong

B. g(x) = 2x + 10
2x + 10 fits x = 2 but rises; g falls.
C. g(x) = −2x + 14
−2x + 14 uses g(2) as the intercept; check x = 2: 10 ≠ 14.
D. g(x) = −3x + 20
−3x + 20 fits x = 2 but gives 5 at x = 5, not 8.

More Algebra questions

Not affiliated with the College Board. SAT is a trademark of the College Board.