Answer:
1
-----
(t+4)^2
Explanation:
(t+3)
------- ÷ (t^2+7t+12)
(t+4)
Copy dot flip
(t+3) 1
------- * --------------------
(t+4) (t^2+7t+12)
Factor
(t+3) 1
------- * --------------------
(t+4) (t+4)(t+3)
Cancel
1 1
------- * --------------------
(t+4) (t+4)
1
-----
(t+4)^2