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 Question from AMANDA, a parent: 15 - (5-x)/ x = 30 I thought you had to multiply both sides by x in order to remove the fraction? 15x - 5x - x2 = 30x then combine 10x - x2 = 30x -x2 =20x then take the sqrt of each side... what am I doing wrong??

Hi Amanda,

Multiplying $\frac{5-x}{x}$ by $x$ gives

$x \times \frac{5-x}{x}.$

The $x$ multiplier and the $x$ in the denominator cancel and hence

$x \times \frac{5-x}{x} = 5-x.$

Hence multiplying both sides of your equation by $x$ yields

$15x - (5-x) = 30x$

Solve for $x.$ Make sure you verify your answer,
Penny

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