Question

find the first term and the nth term of the ap where 9th term and 20th term and 20 and 59 respectively

Answer 1

9th term = a+8d=20
20th term=a+19d=59
subtracting both the equation

Answer 2

a+8d=20 and a+19d =59
subtracting both the equation we get
d=39/11
substitute d value in any equation we get
a=20_312/11
a=92/11