the 4th term of an A.p is 8,the sum of first 12 terms is 126.Find the A.p

Answer 1

Help me solve it out

Answer 2

Just use the formulas you know, and what they have told you.
a+3d = 8
12/2 (2a+11d) = 126
Now just solve for a and d.

Answer 3

a + 3 d = 8 ... 12 a + 36 d = 96

12 a + 66 d = 126

subtracting equations ... 30 d = 30

substitute back to find a

Answer 4

I don't understand pls