In y = ax +b when are a, -b/a, b in arithmetic progression. The
polynomial y = ax^2 + bx + c has roots r1 and r2. Can a, r1, b, r2
and c be in arithmetic progression?
What have Fibonacci numbers to do with solutions of the quadratic
equation x^2 - x - 1 = 0 ?
Observe symmetries and engage the power of substitution to solve