Question

10. Suppose that y varies directly with x. When y is 12, x is -3. What is y when x is 4?

Answer 1

Answer:

y = -16

Step-by-step explanation:

Given that,

y varies directly with x. Mathematically, we can write it as follows :

$y\propto x$

or

$y=kx$

Where

k is constant

Put y = 12 and x = -3 to find k. So,

$k=\dfrac{y}{x}\\\\k=\dfrac{12}{-3}\\\\k=-4$

Now put k = -4 and x = 4. So,

$y=-4\times 4\\\\=-16$

So, the required value of y is equal to -16.