The sum of the first 4 term of linear sequence (A.P) is 26 and that of the next 4 term is 74. Find the common difference
4 a + 6 d = 26
4 a + 22 d = 74
subtract the equations (to eliminate a) , then solve for d
4 a + 22 d = 74
subtract the equations (to eliminate a) , then solve for d