You will need

- The length of the major base, the midline, the height of a trapezoid, area of trapezoid

Instruction

1

The easiest way to find the small base, knowing the large base

**of the trapezoid**and its mid. Property**of a trapezoid**, its middle line is equal to the sum of the bases. Then the small base**of the trapezoid**can be expressed as: b = 2m-a, where m is the middle line**of a trapezoid**, a large base**of the trapezoid**.2

If you know the area

**of a trapezoid**, the height and length of a large base, it is enough to find the small base. According to the formula area**of a trapezoid**S = h(a+b)/2. Therefore, b = (2S/h)-a.3

Let the trapezoid ABCD is angled (as shown). Then its small base can be calculated through a large, elevation and angles with a large base (let's call them x and y).

In this case, the length of the small base can be represented using this data is: b = a-h*(ctg(x)+ctg(y)).

In this case, the length of the small base can be represented using this data is: b = a-h*(ctg(x)+ctg(y)).

4

Now let the notch-line (assume that the angle y is stupid). In this case, the small base can be expressed as: b = a-h(ctg(x)-ctg(180-y)).