the third term of an A.P is a 9 while the eleventh term is -7,find the first five term of A.P

Answer 1

there are 8 differences between the 3rd and 11th terms

-7 - 9 = -16 ... -16 / 8 = -2 ... this is the common difference

start with the 3rd term (9)
... go down two differences ... by subtracting ... 9 - (-2) , 9 - (-2) - (-2)
... go up two differences ... by adding ... 9 + (-2) , 9 + (-2) + (-2)