Question

in an ap if d equal to minus 2 n is equals to 5 and An equals to zero then find the value of a

Answer 1

d=-2, n=5, an=0
 
an=a+(n-1)d
0=a-8
a=8

Answer 2

An=a+(n-1)d
0=a+(5-1)-2
0=a+4(-2)
0=a-8
a=8