Question

If x is directly proportional to y and x = 4.5 when
y = 3, find
(i) an equation connecting x and y,
(ii) the value of x when y = 6,
(iii) the value of y when x = 12.​

Answer 1

$\huge{\boxed{\mathcal\pink{\fcolorbox{red}{blue}{..!!Hello Dear!!...}}}}$${\bold{\huge{\blue{\underline{\red{...!!!!!A}\green{ns}\purple{wer}\orange{!!!!!...}}}}}}$

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$\huge\bold\green{{solution:-}}$

(i) Given that,

x is directly proportional to y

Therefore,

$x \propto y \\\\x = ky ------ eqn\ 1$

${x = 4.5}$ when ${y = 3}$

Substitute in eq 1

${4.5=k×3}$

${k=1.5}$

Substitute k = 1.5 in eq 1

${x = 1.5y}$

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(ii) when ${y=6}$

${x=1.5×6}$

$\huge\bold\orange{{x=9}}$

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(iii) when ${x=12}$

${y=1.5×12}$

$\huge\bold\red{{y=18}}$

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