WAEC Mathematics 2005 Question 12

Question 12

Indices

Solve the equation 27 = 85−x.

  1. A.5/8
  2. B.8/3
  3. C.3/2
  4. D.15/4
Show the answer and explanation

Answer: B (8/3)

Explanation

85−x = 215−3x, so 7 = 15 − 3x and x = 8/3.