The Total solution for NCERT class 6-12
⇒ -x2 + 25x + 54 = 210
⇒ x2 – 25x + 156 = 0
⇒ x2 – 12x – 13x + 156 = 0
⇒ x(x – 12) -13(x – 12) = 0
⇒ (x – 12)(x – 13) = 0
⇒ x = 12, 13
Therefore, if the marks in Maths are 12, thenmarks in English will be 30 – 12 = 18 and the marks in Maths are 13, then marksin English will be 30 – 13 = 17.