Question

can someone help me in finding the process in finding the area for a triangle, trapezoid, circle and rectangle

Answer 1

you mean trapezium

Answer 2

The area of a trapezoid (aka trapezium) is the height times the average of the bases.
area = h (a+b)/2

Now, a rectangle is just a trapezoid where both the top and bottom bases are the same. So, a=b and

area = h(a+a)/2 = h*a or height times width

Similarly, a triangle is just a rectangle with a top base of zero, so

area h (a+0)/2 = ha/2 or, 1/2 base times height

A circle is a different animal, with

area = πr^2

where r is the radius

Answer 3

Steve, thanks for the formulas but I already came up with them, my teacher just wanted me to show the process in which to find the area.