The perpendicular distance from the base to the opposite highest point is called the height ( h ).
Perimeter = a + b + c
Area = ½bh
The perimeter ( P ) is the distance around the outside of the parallelogram.
P = 2a + 2b
The height ( h ) is the perpendicular distance from one parallel side to it's opposite side.
Area = b x h
It is important to measure the correct side in this calculation. In the figure, the height is measured from side b to the opposite side b, so the Area is calculated as b x h, not a x h. If the height was measured from a to a, then the Area would be a x h. Convention considers the side the height is perpendicular to is called the 'base' and usually denoted with a b.
The perimeter ( P ) is the distance around the outside of the rectangle.
P = 2h + 2w
Area = h x w
Perimeter = 4s
Area = s2
The perpendicular distance between the two parallel sides is called the height ( h ).
Perimeter = a + b1 + b2 + c
Area = ½( b1 + b2 ) x h
Circumference ( c ) is the distance around the outside of the circle.
Diameter ( d ) is the distance of the line through the center of the circle from edge to edge.
Radius ( r ) is the distance from the center of the circle to the edge.
The ratio between the circumference and the diameter is equal to the number π.
d = 2r
c = πd = 2πr
Area = πr2
The shortest distance between the center of an ellipse to the edge is called the semiminor axis ( r1 )
The longest distance between the center of an ellipse to the edge is called the semimajor axis ( r2 )
Area = πr1r2
Perimeter = 6r
Area = (3√3/2 )r2
Perimeter = 8a
Area = ( 2 + 2√2 )a2