Question

in an a.p if the d=-4 and the seventh term is 4 find the first term

Answer 1

a+6d=4
then putting the value of d
a+6*-4=4
a=4+24
a=28
then 1st term is 28

Answer 2

d=-4 a7=4 a+6d=4 a+6×-4=4 a-24=4 a=28