tolong ya yg bisa jawab.. minta cara nya doung....

a. 4pq^2 + 6pqr = 2pq ( 2q + 3 r )
b, 4a^2 - 9b^2 = (2a)^2 - (3b)^2
c. x^2 -6x + 9
= ( x -3 )(x -3)
d, x^2 +5x +6
= (x + 2) (x + 3)
e. 2p^2 -9pq + 7q^2
= 2p^2 - 2pq - 7pq + 7q^2
= 2p (p - q) - 7q (p - q)
= (2p -7q)(p-q)