Question

Find the difference.
$(3s^{2} +2st+5t^{2} )-(-2s^{2} +st+7t^{2} )$

Possible Answers:
A: $5s^{2} +st-2t^{2}$
B: $s^{2} +st-2t^{2}$
C: $5s^{2} +3st+12t^{2}$
D: $s^{2} +3st+12t^{2}$

Answer 1

the answer is letter A: 5s^2+st-2t^2