Perimeter

K = 2 ⋅ ( s 1 + s 2 ) {\displaystyle K=2\cdot (s1+s2)}

Luas

L = a ⋅ t {\displaystyle L=a\cdot t}

Tinggi

h a = b ⋅ sin ⁡ ( α ) {\displaystyle h_{a}=b\cdot \sin(\alpha )}

h b = a ⋅ sin ⁡ ( β ) {\displaystyle h_{b}=a\cdot \sin(\beta )}

Diagonal

e = a 2 + b 2 − 2 ⋅ a ⋅ b ⋅ cos ⁡ ( β ) = a 2 + b 2 + 2 ⋅ a ⋅ b ⋅ cos ⁡ ( α ) {\displaystyle {\begin{array}{ccl}e&={\sqrt {a^{2}+b^{2}-2\cdot a\cdot b\cdot \cos(\beta )}}\\&={\sqrt {a^{2}+b^{2}+2\cdot a\cdot b\cdot \cos(\alpha )}}\end{array}}}

f = a 2 + b 2 − 2 ⋅ a ⋅ b ⋅ cos ⁡ ( α ) = a 2 + b 2 + 2 ⋅ a ⋅ b ⋅ cos ⁡ ( β ) {\displaystyle {\begin{array}{ccl}f&={\sqrt {a^{2}+b^{2}-2\cdot a\cdot b\cdot \cos(\alpha )}}\\&={\sqrt {a^{2}+b^{2}+2\cdot a\cdot b\cdot \cos(\beta )}}\end{array}}}

Sudut dalaman

α = γ , β = δ , α + β = 180 ∘ {\displaystyle \alpha =\gamma ,\quad \beta =\delta ,\quad \alpha +\beta =180^{\circ }}

Persamaan segi empat selari

e 2 + f 2 = 2 ⋅ ( a 2 + b 2 ) {\displaystyle e^{2}+f^{2}=2\cdot (a^{2}+b^{2})}