Question

if the sum of 3rd and 10th terms of an increasing ap is 39 while the difference between their 7th and 11th terms 12 find the second term​

Answer 1

Answer:

Step-by-step explanation:

a3+a10=39

a+(3-1)d +a+(10-1)d=39

2a+11d=39. (Let equation 1)

a7-a11=12

a+(7-1)d-a-(11-1)d=12

-4d=12

d=-3

Substitute d=-3 in equation 1

2a+11(-3)=39

2a=72

a=36

2nd term is

a2=a+(2-1)d

=36 -3

=33

Answer 2

Answer:

33

Step-by-step explanation:

a3+a10=39

a1+2d+a1+9d=39

2a1+11d=39

a7-a11=12

a1+6d-(a1+10d)=12

a1+6d-a1-10d=12

-4d=12

d=-3

2a1+11(-3)=39

2a1+(-33)=39

2a1=72

a1=36

a1+d=a2

36-3=a2

33