hello please help

[untold crypt]

Hello if anyone is reading this I needs help I can't understand how to get the solutions and answers since Idk how to properly solve this equation the example given was different here's the given and exmapls thank you

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[stone oyster]

just use logic

r varies directly with s and inversely with the square of u, so $r=k\frac{s}{u^2}$ for some constant $k$

[hasty yoke]

Omegabet_

[stone oyster]

the given data determines k, hence you know the entire relationship

[untold crypt]

Yes but the square though it throws me off guard like do I square first or multiply first then square?

[stone oyster]

wdym

[untold crypt]

Like in the example given

[stone oyster]

you'd replace y with u^2

[untold crypt]

They multiply the value of Z with the denominator

[stone oyster]

cause it varies inversely with u*^2*

you mean when they cross multiply?

that's just them getting rid of the denominator to solve for k

[untold crypt]

So how do I do that?

[stone oyster]

well do you agree it's r=ks/u^2?

[untold crypt]

Yes

[stone oyster]

sub in the givens

and solve for k

$2=\frac{18k}{2^2}$

[hasty yoke]

Omegabet_

[untold crypt]

Ok but

The cross multiply thing how do I do it?

[stone oyster]

just multiply both sides by the denominator.

like... a/b = c/d, you want to get rid of the denominators

multiplying both sides by b gives a=bc/d, and multiplying by d gives ad=bc

so multiplying a/b = c/d by bd gives (abd)/b = (bcd)/d -> ad=bc

[untold crypt]

Oh ok thanks

[stone oyster]

+close