Question

factorise:25a²-9b²+12bc+4c²

Answer 1

Step-by-step explanation:

25a^2-9b^2+4c^2 +12bc

25b^2 -(3b)^2+(2c)^2 +2×3b×2c

{ (a+b)^2 = a^2+b^2 +2ab }

25b^2 -{ ( 3a+2c)^2}