Factorise the following using appropriate identities: 9y2–6y+1
(3y-1) (3y-1)
(2y-1) (3y-1)
(4y-1) (3y-1)
(7y-1) (3y-1)
9y2–6y+1=(3y)2–2(3y)(1)+12
we have (a−b)2=a2–2ab+b2 ⇒(3y−1)2=(3y)2–2(3y)(1)+12
OR
(3y)2–2(3y)(1)+12=(3y−1)2=(3y−1)(3y−1)
Solve the equation 13(y−4)−3(y−9)−5(y+4)=0.