List of formulas in elementary geometry

This is a short list of some common mathematical shapes and figures and the formulas that describe them.

Two-dimensional shapes

Shape	Area	Perimeter/Circumference
Square (where $s$ is the length of a side)	$A=s^{2}$	$P=4s$
Rectangle ( $l$ is length, $w$ is width)	$A=lw$	$P=2l+2w$
Circle (where $r$ is the radius and $d$ is the diameter)	$A=\pi r^{2}$	$C=2\pi r$ or $C=\pi d$
Ellipse (where $a$ is the semimajor axis and $b$ is the semiminor axis)	$A=\pi ab$
Triangle ($b$ is base; $h$ is height; $a,b,c$ are sides)	$A={\frac {bh}{2}}$	$P=a+b+c$
Parallelogram ($b$ is base, $h$ is height, $a$ is side)	$A=bh$	$P=2a+2b$
Trapezoid (where $a$ and $b$ are the bases)	$A={\frac {a+b}{2}}h$

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Three-dimensional shapes

Shape	Volume	Surface area
Cube (where $s$ is the length of a side)	$V=s^{3}$	$6s^{2}$
Rectangular Prism ($l$ = length, $h$ = height, $w$ = width)	$V=lwh$	$S=2lw+2lh+2wh$
Sphere (where $r$ is the radius)	$V={\frac {4\pi r^{3}}{3}}$	$S=4\pi r^{2}$
Right circular cylinder (where $r$ is the radius and $h$ is the height)	$V=\pi r^{2}h$	$S=2\pi rh+2\pi r^{2}$

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