Trapeze – the geometrical figure representing a quadrangle which has two parties which are called the bases are parallel, and two others – are not parallel. They are called trapeze sides. The piece which is carried out through the middle of sides is called the average line of a trapeze. The trapeze can have different lengths of sides or identical, in this case it is called ravnoboky. If one of the parties – is perpendicular to the basis, then the trapeze will be rectangular. But where the nobility is more practical how to find the area of a trapeze.
It is required to you
- Ruler with millimetric divisions
Instruction
1. Measure all parties of a trapeze: AB, BC, CD and DA. Write down results of the measurements.
2. On a piece of AB note the middle – K point. On a piece of DA note a point of L which is on AD midpoint too. Connect points of K and L, the received piece of KL will be the average line of a trapeze of ABCD. Measure KL piece.
3. From trapeze top – melancholy With lower a perpendicular on its basis of AD about SE piece. It will be ABCD trapeze height. Measure SE piece.
4. Let's call KL piece letter m, and SE piece – letter h, then S trapezes of ABCD calculate the area on a formula: S=m*h where m is the average line of a trapeze of ABCD, h is ABCD trapeze height.
5. There is one more formula allowing to calculate the area of a trapeze of ABCD. The lower basis of a trapeze - we will call AD letter b, and the top basis of BC – a letter and. The area we will determine by formula S=1/2 * (a+b) of *h where an and b - the bases of a trapeze, h - trapeze height.