2015 · Q86
If a-b =4 and a²+b²=40 where a and b are positive integers, then a³+b^6 is equal to
Elementary MathematicsAlgebra
- A264
- B280
- C300
- D324
Explanation
(a−b)² = 16 = 40 − 2ab gives ab = 12; with a − b = 4, {a, b} = {6, 2}; a³ + b⁶ = 216 + 64 = 280 (option B).