Question

How to find the area of a rectangle, square, triangle, trapezoid, semi-circle and quarter-circle?

Answer 1

The formula for calculating the area of a square or a rectangle is:

`A=L\cdot W`

in which l is the length and w the width.

To calculate the area of a triangle we use the fomula

`A=(b\cdot h)/(2)`

in which b is the base of the triangle and h is the height of the triangle.

The area of a trapezoid is calculated by the formula

`A=((a+b)\cdot h)/(2)`

in which a is the shortest base, b is the longest base and h is the height.

Finally the are of a circle is calculated by the formula

`A=\pi\cdot r^2`

if it is a semi-circle we divide pi by a half, which results as

`A=(\pi)/(2)\cdot r^2`

same happens for a quarter-circle, but we divide it by 4, it results as

`A=(\pi)/(4)\cdot r^2`

for the 3 of them r represents the radius of the circle.