Originally the dimensions of a rectangle were 20cm by 23cm. When both dimensions were decreased by the same amount, the area of the rectangle decreases by 120. Find the dimensions of the rectangle.
The answer is 17cm by 20cm. The original area is 460cm (20x23), minus 120cm gives a new area of 340cm. 20cm-3cm=17cm and 23cm-3cm=20cm 17cmx20cm = 340cm
