suppose y varies directly with x, and y=10 when x= -3 what direct variation equation relates x and y? what is the value of y when x= -1?

Question

hba · Answer

$$\huge\ y \alpha x$$

$$\huge\ y=kx$$

$$\huge\ k=y/x$$

Here y=10 and x=-3 so just plug them in :)

hba · Answer

So what do you get :)

hba · Answer

Where are you confused ?

hba · Answer

Well let me explain

 y varies directly with x

means

$$y \alpha x$$

Where $$\ \alpha \ is \ the \ sign \ of \ proportionality.$$


So when we remove this sign we have to put a constant  with the equals sign

So let the constant is k

so,

$$y=kx$$

and

$$k=y/x$$