Respuesta :

[tex]a_1=-7 \\ a_2=-2 \\ \\ d=a_2-a_1=-2-(-7)=5 \\ \\ \\ S_{25}= \cfrac{2(-7)+(25-1)5}{2}\cdot25 = \cfrac{-14+120}{2}\cdot25 =\cfrac{106}{2}\cdot25 =1325[/tex]

Your answer is B. 1325