The sum of first four terms of a linear sequence is 26 and that of the next four terms is 74.find the value of the first term and the common difference

4 answers

2(2a + 3D) = 26
2a+3d = 13 **

4(2a + 7d) = 74 + 26 = 100
2a + 7d = 25 ***

Subtract ** from *** to find a and d
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