1. To find the missing base length of a trapezoid (called a trapezium in the UK) if you know other base and midsegment
1. To find the missing base length of a trapezoid (called a trapezium in the UK) if you know other base and midsegment
, 
- bases of a trapezoid
- middle line
Formulas for trapezoid base. Click on the formula image to use the calculator.
2. To find the legs and bases of a trapezoid (trapezium UK) with height, angle and other sides
, - bases
, 
- legs of a trapezoid
, 
- angles at the base
- height
Formulas for trapezoid base if given height, base angle and other base
Formulas for trapezoid base if given leg, base angle and other base
Formulas for trapezoid legs if given base angles and other leg
Formulas for trapezoid legs if given base angles and height
3. To find bases of a trapezoid (trapezium UK) with height, diagonals and angle between them
, - bases
, 
- diagonals
, 
- angles between the diagonals
- height
Formulas for calculating trapezoid base if given height, diagonals and angle between them
* It is true in this case:
