If y -1x and x - 7 when y - 9- find the constant of variation k-

y ∝1x ⇒ y = kx Where, k = constant of variation ∴ #160;(Put x = 7, y = 9) k = xy ∴ #160;k = 7 × 9 ∴ #160;k = 63 ...

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Standard VIII

Mathematics

Direct Proportion

If y ∝1x an...

Question

If $y \propto \frac{1}{x}$ and x = 7 when y = 9, find the constant of variation (k).

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Solution

$y \propto \frac{1}{x}$
$\Rightarrow y = \frac{k}{x}$
Where, k = constant of variation
$∴ (P u t x = 7, y = 9)$
$k = x y$
$∴ k = 7 \times 9$
$∴ k = 63$

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If y∝1x and x = 7 when y = 9, find the constant of variation (k).

y∝1x⇒y=kxWhere, k = constant of variation∴(Put x=7,y=9)k=xy∴k=7×9∴k=63

If $y \propto \frac{1}{x}$ and x = 7 when y = 9, find the constant of variation (k).

$y \propto \frac{1}{x}$
$\Rightarrow y = \frac{k}{x}$
Where, k = constant of variation
$∴ (P u t x = 7, y = 9)$
$k = x y$
$∴ k = 7 \times 9$
$∴ k = 63$