Question 191883
Factor completely:
{{{25a^2+64-80a}}} Rewrite as:
{{{25a^2-80a+64}}} Notice that the coefficient of {{{a^2}}} is a perfect square: {{{25 = 5^2}}} and the constant term is a perfect square: {{{64 = 8^2}}}, so try:
{{{highlight(25a^2-80a+64 = (5a-8)(5a-8))}}} or {{{highlight((5a-8)^2)}}}