The equations that show a direct variation between x and y when solved for y are:
A. -10+y=3x-10
B. y=-1/8x
Since k is constant (the same for every point), we can find k when given any point by dividing the y-coordinate by the x-coordinate. For example, if y varies directly as x , and y = 6 when x = 2 , the constant of variation is k = = 3 . Thus, the equation describing this direct variation is y = 3x .