Question

How do I solve this equation? (equation in response)

Answer 1

\[\frac{ 4}{ 5}=\frac{ 8}{ x}\]

Answer 2

Do you have any idea?

Answer 3

4*2=8 5*2=10 when ever you multiply 2 by the denominator or numerator you do the other side

Answer 4

Well, I figured I would cross multiply but, I do not know for sure.

Answer 5

Cross-multiplication would be a good way.

Answer 6

I explained it to him also whpalmer so please don't be rude to me.

Answer 7

As far as I know no one was rude to any one.

Answer 8

Or just multiply both sides by 5:
\[\frac{4}{5}*5 = \frac{8}{x}*5\]\[\frac{4}{\cancel{5}}*\cancel{5} = \frac{40}{x}\]\[4 =\frac{40}{x}\]\(x\) must be \(10\) for that to work, right?

@masterlot168 No one is being rude, except possibly you.

Answer 9

I wasn't being rude i just said please don't ive been looking at other comments and I didn't mean to say rude I really meant like correction or anything else.

Answer 10

What @masterlot168 is showing is that if you look at your two fractions:

\[\frac{4}{5}\]and\[\frac{8}{x}\]multiplying the numerator of the first fraction by 2 will give you the numerator of the second fraction. That means you can multiply the denominator of the first fraction by 2 and the result will be equal to the denominator of the second fraction, which is \(x\).

\[\frac{4}{5} * \frac{2}{2} = \frac{8}{x}\]\[\frac{4*2}{5*2} = \frac{8}{x}\]\[\frac{8}{10}=\frac{8}{x}\]Therefore, \(x=10\)

Multiplying by a fraction consisting of any non-zero number divided by itself is equivalent to multiplying by 1, because that fraction has the value 1. It doesn't change the value, only the way the value is expressed, which may make it more convenient.

Answer 11

So, if I were to cross multiply would I get this?\[\frac{ 4 }{ 5}=\frac{ 8 }{ x}--[4*x = 4x : 5*8=40]-- \frac{ 40 }{ 4x}=10\]

Answer 12

Pretty sure I would.

Answer 13

Yes.
\[\frac{4}{5} = \frac{8}{x}\]\[4*x = 5*8\]\[4x=40\]\[x=\frac{40}{4} = 10\]