passwella.
Menu

WAEC Further Mathematics 2011 Question 10

Question 10

Functions

f(x) = p + qx, where p and q are constants. If f(1) = 7 and f(5) = 19, find f(3).

  1. A.13
  2. B.15
  3. C.17
  4. D.26
Show the answer and explanation

Answer: A (13)

Explanation

p + q = 7 and p + 5q = 19 give 4q = 12, q = 3 and p = 4. So f(3) = 4 + 9 = 13.