Let y varies directly as x If y = 15 when x = 3, then write a linear equation - Maths - Linear Equations in Two Variables

Question

Let y varies directly as x If y = 15 when x = 3, then write a
linear equation What is the value of y when x = 5?

Ayush Jha · Accepted Answer

It is given that y is directly proportional to x. So,

$y \propto x$

Therefore taking a constant k to get,

$y = k x$

.If y=15,when x=3 than the value of the constant is-

$15 = 3 k k = 5$

Therefore the linear equation is-

$y = 5 x$

Hence the value of y when x=5 is-

$y = 4 (5) = 25$

Let y varies directly as x. If y = 15 when x = 3, then write a linear equation. What is the value of y when x = 5?