How do you solve $12/21= (x-5)/x$ ?

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Answer 1 · 2016-03-10T18:50:39

$x = 105/9 or 11(6)/9 or 11(2)/3$

$12/21 = (x-5)/x$

Cross multiply to eliminate the denominators.
$12(x) = (x-5)21$

Use distributive property to eliminate the ( ).
$12x = 21x - 105$

Combine like terms.
$12x - 21x = cancel(21x) - cancel(21x) - 105$

$-9x = -105$

Divide by the coefficient to isolate the variable.
$(cancel(-9)x)/cancel(-9) = -105/-9$

$x = 105/9 or 11(6)/9 or 11(2)/3$

How do you solve 12/21= (x-5)/x12/21= (x-5)/x?