Trapezoid diagonal e calculation

Calculator and formulas for the diagonal e of a trapezoid using side length and height

Caculate Diagonale e


This function calculates the diagonal e of a trapezoid using the lengths of the sides and the height. For the calculation, enter the lengths of the two sides a and b and the height. Then click the 'Calculate' button


Caculate Diagonal e

 Input
Side length a
Side length b
Height h
Decimal places
 Results
Diagonal e

Formulas for calculating the diagonal e using sides and height


Using the side length a and b

The diagonal e forms a right triangle with the height h and the side (a - y) . The diagonal e forms the hypotenuse and can be calculated according to the Pythagorean theorem.

First, the length of y has to be calculated, which in turn can be calculated from b and h :

\(\displaystyle y =\sqrt{b^2-h^2} \)

The diagonal e can now be calculated using the following formula:

\(\displaystyle e =\sqrt{(a-y)^2+h^2} \)

Use of the side lengths c and d

Alternatively, you can calculate with the side lengths c and d . To do this, the leg of the left triangle is first calculated:

\(\displaystyle x =\sqrt{d^2-h^2} \)

In the following formula, x is added to the side length c .

\(\displaystyle e =\sqrt{(c+x)^2+h^2} \)

Formula for calculating the diagonal e using the angle

If the height is not known, the diagonal e can be calculated using the an angle.

\(\displaystyle e =\sqrt{(a^2+b^2) - (2 · a · b · cos(β))} \)

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