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2 votes
Thirty times the square of a non-zero number is equal to eight times the number. what is the number?

User GDmac
by
6.8k points

2 Answers

6 votes
Hello,

let x the unknowed number,

30*x²=8*x
==> 30x=8 (for x ≠0)
==>x=8/30
==>x=4/15

Confusion dans la traduction mentale désolé.

User Richard Szalay
by
6.2k points
7 votes
You said that 30 x² = 8 x

I can divide
each side by 'x': 30 x = 8

Then divide
each side by 30: x = 8 / 30 = 4/15 .

Check to see if it works:

Does 30 (4/15)² = 8 (4/15) ?

Well, (4/15)² = 16/225

30 · 16/225 = 480/225 = 32/15
and
8 · 4/15 = 32/15 yay !
User JustH
by
6.4k points
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