# Area of a trapezium

• Oct 25th 2007, 03:30 AM
dravid2
Area of a trapezium
How do you work out the area of a trapezium.

An example would be good as well.

• Oct 25th 2007, 09:08 AM
Spimon
The formula is 1/2 (a+b) * h

http://img147.imageshack.us/img147/9558/trapbd2.jpg

Example:
Area = 1/2*(5+8)*3
= 1/2*(13)*3
= 19.5 units squared

http://img517.imageshack.us/img517/7385/examplejq4.jpg
• Oct 25th 2007, 09:13 AM
Sean12345
Let a and b be the parallel sides of the trapezium.
Let h be the height of the trapezium.

$A=\frac{h(a+b)}{2}$

Example: A trapezium of height 6cm has 2 parallel sides one is 10cm the other is 8cm. Find the area of the trapezium.

Using the formula:

$A=\frac{h(a+b)}{2}$

$A=\frac{6(10+8)}{2}$

$\implies A=\frac{6(18)}{2}$

$\implies A=\frac{108}{2}$

$\implies A=54cm^2$
• Oct 25th 2007, 10:07 AM
dravid2
thx a lot m8, that was loadz of help