(x + 12)²

(x - 12)²

(x + 15)²

(x + 13)²

x²+16

x²-16

x²+8x+16

x²+8x-16

u²-25v²

u²+25v²

u²-10uv+25v²

u²+10uv+25v²

9m² – 1

9m² – 6m – 1

9m² + 1

9m² + 6m – 1

 $\left(9t-25\right)^2$  

 $\left(3t-5\right)^2$  

 $\left(3t-5\right)\left(3t+5\right)$  

 $\left(9t-25\right)\left(9t+25\right)$  

 $3\left(z^2-9\right)$  

 $\left(3z-9\right)\left(z+3\right)$  

 $3\left(z+9\right)\left(z-9\right)$  

 $3\left(z+3\right)\left(z-3\right)$