Question

Determine whether y varies directly with x. If so, find the constant of variation k and write the equation.
The table ges right side dwnards, 7,8,9,10
the left side dwn ges 11, 13, 15, 17
Now I understand it I just don't knw how t write it. Help please

Answer 1

obviously not direct variation. If x=in and y=out, it is clear that y changes by 2 when x changes by 1, so

y = 2x + some offset.

Looking at x=7, we see that

y = 2x - 3