(ii) 9a2+16b29a^2 + 16b^2 9a2+16b2 Solution Write as difference of squares:9a2+16b2=(3a)2−(−16b2)=(3a)2−(4ib)2Factor:=(3a−4ib)(3a+4ib)\begin{aligned} & \boxed{\text{Write as difference of squares:}} \\ \\ & 9a^2 + 16b^2 = (3a)^2 - (-16b^2) = (3a)^2 - (4ib)^2 \\ \\ & \boxed{\text{Factor:}} \\ \\ & = (3a - 4ib)(3a + 4ib) \end{aligned}Write as difference of squares:9a2+16b2=(3a)2−(−16b2)=(3a)2−(4ib)2Factor:=(3a−4ib)(3a+4ib)