Question

Sum of 5th and 9th term of an ap is 72 and the sum of 7 th and 12th term of same ap is 97.find the first 4 terms

Answer 1

Step-by-step explanation:

a5= a+4d

a9= a +8d

a5+a9=72

a+4d+a+8d=72

2a+12d=72

a+6d=36...............(1)

a7=a+6d

a12= a + 11d

a7+a12= 97

a+6d+a+11d= 97

2a+17d=97...................(2)

eliminate the equation 1 and 2 ...

you will get a and d...

then put them ...

as a1=a

a2 = a+ d

a3= a+2d

a4= a+ 3d

and you will get it....

hope it'll help you.....