`1.  Side (base) of an isosceles trapezoid if you know other base and midline of a trapezoid  `

,      -  bases

- midline

Calculate the base of an isosceles trapezoid if given middle line and other base  ( a b  ) :

`2.  All four sides of an isosceles trapezoid if you know height, angle at the base and other sides  `

- smaller base

- larger base

-  leg

-  angle  at the base

- height

Calculate the lateral side (leg) of a trapezoid if given angle at the base, height or bases  ( c  ) :

Calculate the base of a trapezoid if given angle at the base, height and other base  ( a b  ) :

Calculate the base of a trapezoid if given angle at the base, lateral side (leg) and other base  ( a b  ) :

`3.  Bases of an isosceles trapezoid if you know height, diagonals and angle between the diagonals  `

- smaller base

- larger base

-  leg

-  diagonal

,      -  angles between the diagonals

- height

Calculate the side (base) of a trapezoid if given diagonal, lateral side (leg) and other base ( a b  ) :

Calculate the lateral side (leg) of a trapezoid if given diagonal and bases ( c  ) :

Calculate the side (base) of a trapezoid if given diagonal, height, angle between the diagonals and base ( a b  ) :

* It is true in this case:

`4.  Sides of an isosceles trapezoid if you know area of a trapezoid  `

,      -  bases

-  leg

-  midline

,      -  angles at the base

- height

- area

Calculate the side (base) of a trapezoid if given area of a trapezoid ( a b  ) :

Calculate the lateral side (leg) of a trapezoid if given area of a trapezoid ( c  ) :

* It is true in this case:

`1.  Lateral side (height) of a right trapezoid if you know bases, other lateral side and angle at the base Â `

Â , Â Â Â - Â bases

Â Â Â - lateralÂ sideÂ =Â height

Â - lateralÂ side

Â Â - Â angle

Â Â Â Â - Â height

Â

Calculate the lateral side (height) of a trapezoid if given bases, other lateral side and angle at the base Â ( Â ) :

Â

Â

`2.  Lateral side (height) of a right trapezoid if you know diagonals, bases and angle between the diagonals Â `

Â , Â Â Â  Â - Â bases

Â Â Â - lateralÂ sideÂ =Â height

Â , Â Â Â  Â - Â diagonals

Â , Â Â Â  Â - Â anglesÂ between the diagonals

Â

Calculate the lateral side (height) of a trapezoid if given diagonals, bases and angle between the diagonals Â ( Â ) :

* It is true in this case:

Â

Â

`3.  Lateral side (height) of a right trapezoid if you know bases or midline and area of a trapezoid  Â `

Â

Â , Â Â Â  Â - Â bases

Â Â Â - lateralÂ sideÂ =Â height

Â - midline

Â Â Â Â - Â areaÂ of a trapezoid

Â

Calculate the lateral side (height) of trapezoid if given bases or midline and area of a trapezoid Â ( Â ) :

Â

Â

`4.  Lateral side of a right trapezoid if you know bases, other lateral side (height) and angle at the base Â `

Â - largerÂ base

Â - smallerÂ base

Â Â Â - lateralÂ sideÂ =Â height

Â - lateralÂ side

Â Â - Â angleÂ  at the base

Â Â Â Â - Â height

Calculate the lateral side of a trapezoid if given bases and lateral side(height)Â :( Â ) :

Â

Calculate the lateral side of a trapezoid if given angle at the base and bases or lateral side (height)Â ( Â ) :

Â

Â

`5.  Lateral side of a right trapezoid if you know area of a trapezoid, angle at the base and bases or midline  Â `

Â , Â Â Â  Â - Â bases

Â Â Â - lateralÂ sideÂ (leg)

Â Â - Â angleÂ  at the base

Â - midline

Â Â Â Â - Â area

Â

Calculate the lateral side of trapezoid if given area of a trapezoid, angle at the base and bases or midline Â ( Â ) :

Â

Â

,      -  bases

=      - lateral side = height

,      -  diagonals

Find the diagonals of a trapezoid if given lateral sides (height) and base, using The Pythagorean Theorem (  ) :

Other formulas for diagonals as for a scalene trapezoid

`1.  Median of a right trapezoid (also known as midline or midsegment) if you know bases  `

,      -  bases

- midline

Find the median of a trapezoid if given bases (  ) :

`2.  Median of a right trapezoid (also known as midline or midsegment), if you know base, lateral sides and angles at the base  `

- larger base

- smaller base

- lateral side

=      - lateral side = height

-  angle at the base

- midline

Find the median of a trapezoid if given base, height and angle at the base (  ) :

Find the median of a trapezoid if given base, lateral side and angles at the base (  ) :

Find the median of a trapezoid if given base and lateral sides (  ) :

`3.  Median of a right trapezoid (also known as midline or midsegment), if you know diagonals, height and angle between the diagonals   `

,      -  diagonals

,      -  angles between the diagonals

- height

- midline

Find the median of a trapezoid if given diagonals, height and angle between the diagonals (  ) :

`4.  Median of an arbitrary trapezoid (also known as midline or midsegment), if you know height and area of a trapezoid  `

- areaof a trapezoid

- height

- midline

Find the median of a trapezoid if given height and area of a trapezoid (  ) :