Geometry Formulas


Here are all the formulas we use in Geometry. There are some *quality core* formulas as well.
Selam H
Flashcards by Selam H, updated more than 1 year ago
Selam H
Created by Selam H about 10 years ago

Resource summary

Question Answer
Standard Form \[Ax+By=C\]
Slope M=\[\frac{y_2-y_1}{x_2-x_1}\]
Slope-Intercept Form \[y=mx+b\]
Point-Slope Form \[y-y_1=m(x-x_1)\]
Distance on a Number Line D=\[|a-b|\]
Distance on a Coordinate Plane D=\[\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}\]
Distance in Space (3D) D=\[\sqrt{(x_2-x_1)^2+(y_2-y_1)^2+(z_2-z_1)^2}\]
Distance Arc Length L=\[\frac{N}{360}·2\pi·r\]
Midpoint on a Number Line M=\[\frac{a+b}{2}\]
Midpoint on a Coordinate Plane M=\[\frac{x_1+x_2}{2},\]\[\frac{y_1+y_2}{2}\]
Midpoint in Space (3D) M=\[\frac{x_1+x_2}{2},\]\[\frac{y_1+y_2}{2},\]\[\frac{z_1+z_2}{2}\]
Perimeter of a Square P=\[4s\] (s=side)
Perimeter of a Rectangle P=\[2l+2w\] (l=length, w=width)
Circumference of a Circle C=\[2\pi·r,\pi·d\]
Area of a Square A=\[s^2, lw\]
Area of a Rectangle A=\[lw, bh\]
Area of a Parallelogram A=\[bh\]
Area of a Trapezoid A=\[\frac{1}{2}h(b_1+b_2)\]
Area of Rhombus A=\[\frac{1}{2}d_1d_2, bh\]
Area of Triangle A=\[\frac{1}{2}bh\]
Area of Regular Polygon A=\[\frac{1}{2}Pa\]
Area of a Circle A=\[\pi·r^2\]
Area of Sector of a Circle A=\[\frac{N}{360}\·pi·r^2\]
Quadratic Formula \[\frac{-b±√b^2-4ac}{2a}\]
Lateral Surface Area of Prism L=\[Ph\]
Lateral Surface Area of a Cylinder L=\[2\pi·r·h\]
Lateral Surface Area of a Pyramid L=\[\frac{1}{2}Pl\]
Lateral Surface Area of a Cone L=\[\pi·r·l\]
Total Surface Area of a Sphere SA=\[4\pi·r^2\]
Total Surface Area of a Hemisphere SA=\[3\pi·r^2\]
Volume of a Pyramid V=\[\frac{1}{3}Bh\]
Volume of a Rectangular Prism V=\[Bh\]
Volume of a Right Circular Cylinder V=\[2\pi·r^2+2\pi·r·h\]
Volume of a Right Circular Cone V=\[\frac{1}{3}·pi·r^2·h\]
Volume of a Sphere SA=\[\frac{3}{4}·pi·r^3\]
Surface Area of a Regular Prism or Cylinder (2-based) SA= \[Ph+2B\] *If you are finding the surface area of a cylinder, replace P (perimiter) with Circumfrance.
Surface Area of a Regular Pyramid or Cone (1-based) A=\[\frac{1}{2}Pl+B\] *If you are finding the surface area of a cone, replace P (perimiter) with Circumfrance **l= slanted height
Pythagorean Theorem \[a^2+b^2=c^2\]
\[\sin A=\]\[\frac{a}{c}\]
\[\cos A=\]\[\frac{b}{c}\]
\[\tan A=\]\[\frac{a}{b}\]
Sum of Degree Measures of the Interior Angles of a Polygon \[180(n-2)\] (n=number of sides)
Degree Measure of an Interior Angle of a Regular Polygon \[\frac{180(n-2)}{n}\]
is perpendicular to
|| is parallel to
is congruent to
is similar to
is approximately equal to
∆ABC triangle ABC
∠ABC angle ABC
m∠ABC the degree measure of angle ABC
Circle O circle with center point O
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