Answer:
Type of variation
1) Direct variation
Simple equation y=Kx
Y varies directly with x
Practical example-
Radius of the circle lit by a car's
Light decreases (y) as the distance away from the garage decreases (c)
2) Inverse variation
Simple equation y=k/x
Y inversely with c
Example- the brightness of a car's light increase (y) as the distance away from the garage decreases (x)
3) Joint variation
Simple equation y=kxz
Y varies jointly with x and z
Example-The heat lose through a glass window (y) varies jointly with the area of the window (x) and the temperature differences between inside and outside
Explanation: