So we want to know the height of the image, Hi, formed by the convex lens. Height of the object is H0=2 cm, distance of the object from the convex lens is D0= 10 cm, focal length of the lens is f= 6 cm and the distance of the image from the lens is Di= 8 cm. The formula for the magnification M of the convex lens is: M= Hi/H0=-(Di/D0). Now we solve the equation: Hi=-(Di/D0)*H0 and plug in the numbers: Hi=-(8/10)*2=-0.8*2=-1.6 cm. So the height of the image is Hi=-1.6 cm. The minus sign tells us the image is inverted.