The area of a parallelogram is measured in the same way as the
area for a rectangle or a square. The height of a parallelogram is
the distance between the two horizontal sides.
As we showed in an earlier section we can divide a square or a
quadrilateral into two triangles. This gives us that the area of a
triangle is half the area of the quadrilateral with the same base
If the area of a parallelogram is A=b ∙ h then the area for a
triangle is A=0.5b ∙h or
A trapezoid is a quadrilateral with two parallel sides. Both
parallel sides are called bases.
To find the area of a trapezoid we need to divide it into two
triangles. Both triangles produced have the height h.
The area of the trapezoid is the sum of the areas of the two
The area of a circle is different from the areas of a triangle
or a quadrilateral. The area formula of a circle is:
We get the area of a circle by multiplying π by the radius, r,
Video lesson: Find the areas