Answer:
(8x+3)²
Explanation:
The polynomial has perfect squares on wither end of the expression including 64 and 9. This means it is likely factoring to (8x +3)². TO check this we will multiply it out.
(8x+3)(8x+3) = 64x² + 24x + 24x + 9 = 64x² + 48x + 9