Question

How symbols, scales and legends are important in a map?

Answer 1

yes,needed in a map the symbols scales

Answer 2

symbol= it is not possible to draw on a map the actual shape and size of different features such as building ,roads,bridges,trees,railway line are not draw in a map.
scales= scale is the ratio between the actual distance on the ground and the distance show on map.
legends= a map or legend is included with a map to unlock it gives you the information needed for the map to make sense