equation [noun] [C] - an equation (= mathematical statement) which includes an unknown value that is multiplied by itself only once, and which does not include an unknown value multiplied by itself more than onceIn the quadratic equation, 2y2+3y=14, y=2 or y=-3½.
QUADRATIC
Meaning of QUADRATIC in English
Cambridge English vocab. Кембриджский английский словарь. 2012