Divide the trapezium into two triangles by a diagonal line; find the area of each of these triangles ; the sum of their areas will be the area of the ... Multiply the perimeter of the polygon by half the perpendicular let fall from the centre upon one of its sides ; the product trill be the area. 1. ... Find the square of the side of the given.
|Title||:||The American Arithmetic|
|Author||:||James Robinson (of Boston.)|