Answer:
9r^2 + 30r+25 = (3r + 5)²
Explanation:
It is given a quadratic equation,
9r^2 + 30r+25 ------(1)
a = 9, b = 30 and c = 25
ac 9 x 25 = 225 = 15 x 15
Splitting middle term
9r^2 + 30r+25 ------(1)
⇒ 9r^2 + 15r + 15r + 25
⇒ 3r(3r + 5) + 5(3r + 5)
⇒ (3r + 5)(3r + 5) = (3r + 5)²