Step-by-step explanation:
[tex] - 20 \: is \: your \: answer[/tex]
Supposition of Terms in an A.P.
(1) Three terms as : a -d, a,a + d .
(2) Four terms as : a -3d , a - d , a + d , a + 3d .
(3)Five terms as : a -2d , a - d , a , a+ d, a + 2d.
To know the solution with Proof
Refer To the above attachment .
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