# Area of a quadrilateral Calculator

## Calculates the area and perimeter of a quadrilateral given four sides and two opposite angles.

 side a side b side c side d sum of angles θ1+θ2 6digit10digit14digit18digit22digit26digit30digit34digit38digit42digit46digit50digit area S perimeter L
 $\normal Bretschneider's\ formula \\\vspace{5}(1)\ area:\ S=\sqrt{(s{\small-}a)(s{\small-}b)(s{\small-}c)(s{\small-}d){\small-}abcd\cos^{\small2}\frac{\theta}{2}}\\\hspace{100} s={\large\frac{a+b+c+d}{2}}\ ,\hspace{10} \theta=\theta_1+\theta_2\\\vspace{5}(2)\ perimeter:\ L=2s=a+b+c+d$
 [1-10] /337 Disp-Num5103050100200
[1]  2018/10/15 16:36   Male / 30 years old level / Self-employed people / Very /
Purpose of use
To calculate material usage for an irregularly shaped area. Worked great, I'll use it again!
[2]  2018/10/14 13:33   Male / 60 years old level or over / An engineer / Very /
Purpose of use
Calculate roof area for materials purchase
Comment/Request
Excellent tool for aid to project
[3]  2018/10/07 02:13   Male / 30 years old level / Elementary school/ Junior high-school student / Very /
Purpose of use
Property purchase purpose
Bug report
Ab=20
Bc=47
Cd=32
Da=37
[4]  2018/08/20 23:37   Male / 40 years old level / Self-employed people / Very /
Purpose of use
Calculate area of a plot of land
[5]  2018/08/20 15:51   Male / 30 years old level / An engineer / Useful /
Purpose of use
Calculating Plot Area
[6]  2018/07/17 01:47   Male / 50 years old level / A retired people / A little /
Purpose of use
Find the area of a piece of property
Comment/Request
I only know one angle.
[7]  2018/07/12 20:56   Male / 40 years old level / Others / Very /
Purpose of use
FOR DIVIDE THE PLOT
[8]  2018/06/14 01:24   Female / 50 years old level / An office worker / A public employee / Very /
Purpose of use
Calculate lot size for client.
[9]  2018/06/12 00:14   Male / 60 years old level or over / Self-employed people / Very /
Purpose of use
Area of land to be leased
[10]  2018/06/04 20:21   Male / 30 years old level / An office worker / A public employee / Very /
Purpose of use
land area

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