Se "y" for inversamente proporcional a "x" e "y" = 15 quando "x" = 5, qual é o valor de "y" quando "x" = 25?

Responda:

$y = 3$ $y=3$

Explicação:

$the initial statement is y \propto \frac{1}{x}$ $"the initial statement is "yprop1/x$

$to convert to an equation multiply by k the constant$ $"to convert to an equation multiply by k the constant"$
$of variation$ $"of variation"$

$\Rightarrow y = k \times \frac{1}{x} = \frac{k}{x}$ $rArry=kxx1/x=k/x$

$to find k use the given condition$ $"to find k use the given condition"$

$y = 15 when x = 5$ $y=15" when "x=5$

$y = \frac{k}{x} \Rightarrow k = y x = 15 \times 5 = 75$ $y=k/xrArrk=yx=15xx5=75$

$"equation is " color(red)(bar(ul(|color(white)(2/2)color(black)(y=75/x)color(white)(2/2)|)))$

$"when "x=25" then"$

$y=75/25=3$