Answer:
-7
Step-by-step explanation:
Answer:
Answer:
D ) 154
Step-by-step explanation:
a 1 = 13, d = 3;
S n = n/2 * ( a 1 + a n )
a 7 = a 1 + 6 d = 13 + 3 * 6 = 13 + 18 = 31
S 7 = 7/2 * ( 13 + 31 ) = 7/2 * 44 = 154
I believe the green one bc it doesn't go into a point from all angles
