The average of a positive numbers (non-zero) and its square is 8 times the number. The number is A) 15 B) 17 C) 13 D) 19

1 Answer

Answer :

A)

Let the number be ‘x’

rThen x+x^2/2 = 8x

X+x^2=16x

X^2=15x

X^2 – 15x = 0

X(x-15)=0

X=0 or x= 15

So the number is 15 (because given [non-zero] positive).


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