2. Then add heat. After 24 hours, use heat to dilate the blood vessels and improve circulation in the area. Warm compresses will help speed up the bodys natural mechanisms for removing the blood in the bruise, says Randy Wexler, M.D.
where k is the constant of variation. 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 .
Here are some examples of direct and inverse variation: 1  Direct: The number of dollars I make varies directly (or you can say varies proportionally) with how much I work. 2  Direct: The length of the side a square varies directly with the perimeter of the square.