Question

the 9th term of an ap is 1 more than 5 times the second term and the 12th term is 7 more than twice the 5th term find the AP​

Answer 1

The ninth term of an AP is equal to seven times the second term and twelfth term exceeds five times the third term by 2. Find the first term and the common difference.

Answers

A9=7*a2

a12=5a3+2

That means,

a9=(a+d)7

a12=5(a+2d)+2

That means,

a+8d=7a+7d, d=6a

a+11d=5a+10d+2,

d=4a+2,

2a=2,

a=1

d=6a=6

So first term is 1 & common difference is 6.