Given:-
suppose y varies directly with x and y=-20 when x=-1.
To find:-
what direction variation equation relates to x and y what is the value of y when x=-10.
y varies directly with x that means y is directly propotional to x.

Value of y=-20 when x=-1, so substituting we get,

So the value of k is 20.
So the direct equation is,

Now we find the value of y when x=-10,

So the value of y is -200.