4 hearts to 6 stars can be reduced, which makes 2 hearts to 3 stars. so you go from 2 hearts : 3 stars to 4 hearts : 6 stars then you would get to 6 hearts : 9 stars.
explanation #2
4:6 can be reduced which equals 2:3. the difference between 2 and 4 is 2 and the difference from 3 and 6 is 3. so 6:9 would be after 4:6
The horizontal axis in the coordinate plane is called the x-axis. The vertical axis is called the y-axis. The point at which the two axes intersect is called the origin. The origin is at 0 on the x-axis and 0 on the y-axis.