Simplify (7t^2 + 9) + (6t^2 + 8).

A. t^2 + 1

B. 13t^2 + 17

C. 13t^4 + 17

D. 42t^2 + 72

The simplified expression is:

(7t^2 + 9) + (6t^2 + 8)
= 7t^2 + 6t^2 + 9 + 8
= 13t^2 + 17

Therefore, the simplified expression is:

B. 13t^2 + 17