The area of a rectangle is calculated by multiplying the measure of the sides. That is the length and the width.
Area = length x width
To determine the measure or length of one pair of parallel sides of the rectangle, the area is divided by the given dimension of the sides.
Length = Area / width
Length = (1575 sq units) / (45 units)
Length = 35 units
Hence, to draw the rectangle, two pair parallel sides will have the lengths of 45 and 35 units.