Question

if a:b::c:d, then proof that (4a+7b):(4a-7b)::(4c+7d):(4c-7d).​

Answer 1

proved a:b::c:d if 4a+7b/4c+7d=4a-7b/4c-7d. If a, b, c, d are in proportion, then prove that a²+5c²/b²+5d²=a/b ...

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