if 9th term of an A. P is zero, show that 29th term is twice its 19th

1.	if 9th term of an A. P is zero, show that 29th term is twice its 19th term.
Answer» Let us assume that its right that 29th term of the AP is twice its 19th term. Then,a+28d = 2(a+18d)..Upon solving, we get,a+8 = 0.., which is already given an is right for this AP(the 9th term is 0).Thus means that our assumption is right.Hence, proved.☺

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