Geometry Formulas

Pythagorean Theorem -

a² + b² = c²

Speed Formula -

s = d/t

Distance Formula -

d = st

Time Formula -

t = d/s

km →m

x1000

m →cm

x100

cm →mm

x10

mm → cm

÷10

cm →m

÷100

m → km

÷1000

1 km =

1000 m

1 m =

100 cm

1 m =

1000 mm

1 cm =

10 mm

1 km² =

1,000,000 m²

1 m² =

10,000 cm²

1 m² =

1,000,000 mm²

1 cm² =

100 mm²

1 kL =

1000 L

1 L =

1000 mL

1 mL =

1 cm³

1 L =

1000 cm³

1 km³ =

1,000,000,000 m³

1 m³ =

1,000,000 cm³

1 m³ =

1,000,000,000 mm³

1 cm³ =

1000 mm³

1 year =

365 days

1 year =

12 months

1 year =

52 weeks

1 week =

7 days

1 day =

24 hours

1 hour =

60 minutes

1 minute =

60 seconds

Perimeter Formula for Triangle -

P = a + b + c

Perimeter Formula for Square -

P = 4s

Perimeter Formula for Rectangle -

P = 2(l+w)

Perimeter Formula for Circle (radius version) -

C = 2πr

Perimeter Formula for Circle (diameter version) -

C = πd

Perimeter Formula for Half a Circle (diameter version) -

P = πd/2 + d

Perimeter Formula for Half (1/2) a Circle (radius version) -

P = 2πr/2 + 2r = πr + 2r

Perimeter Formula for a quarter (1/4) of a Circle -

P = 2πr/4 + 2r = πr/2 + 2r

Perimeter Formula for a Sector -

P = θ/360° x 2πr + 2r

Area Formula of Rectangle -

A = lw or bh

Area Formula of Triangle -

A = bh/2

Area Formula of Parallelogram -

A = bh

Area Formula of Trapezoid -

A = (a+b)/2 x h

Area Formula of Circle -

A = πr²

Area Formula for Half (1/2) of Circle -

πr²/2

Area Formula for a Quarter (1/4) of Circle -

πr²/4

Surface Area Formula for Cube -

SA = 6x²

Surface Area of Rectangular Prism -

SA = 2(lw + wh + hl)

Surface Area Formula for Whole Cone -

πr² + πrs

Surface Area Formula for Side of Cone -

SA = πrs

Surface Area Formula for Solid Cylinder -

SA = 2πr² + 2πrh

Surface Area Formula for Side Part and Bottom of Cylinder -

SA = πr² + 2πrh

Surface Area Formula for Side Part of Cylinder -

SA = 2πrh

Surface Area Formula for Sphere -

SA = 4πr²

Volume Formula for Solid of Uniform Cross-Section -

V = Ah or Al

Volume Formula for Cube -

V = x³

Volume Formula for Rectangular Prism -

V = lwh

Volume Formula for Triangular Prism -

V = bh/2 x l

Volume Formula for Cylinder -

V = πr²h

Volume Formula for Cone -

V = 1/3π²h

Volume Formula for Square-Based Pyramid -

V = 1/3 Ah

Volume Formula for Sphere -

V = 4/3πr³

of Sides in a Triangle -

3 sides

of Sides in a Quadrilateral -

4 sides

of Sides in a Pentagon -

5 sides

of Sides in a Hexagon -

6 sides

of Sides in a Heptagon -

7 sides

of Sides in an Octagon -

8 sides

Sum of Interior Angles in a Triangle -

S₃ = 180°

Sum of Interior Angles in a Quadrilateral -

S₄ = 360°

Sum of Interior Angles in a Pentagon -

S₅ = 540°

Sum of Interior Angles in a Hexagon -

S₆ = 720°

Sum of Interior Angles in a Heptagon -

S₇ = 900°

Sum of Interior Angles in an Octagon -

S₈ = 1080°

Sum of Interior Angles in a n-sided polygon -

Sₙ - 180° (n - 2)

Sum of Exterior Angles in a Triangle -

E = 360°

Sum of Exterior Angles in a Quadrilateral -

E = 360°

Sum of Exterior Angles in a Pentagon -

E = 360°

Sum of Exterior Angles in a Hexagon -

E = 360°

Sum of Exterior Angles in a Heptagon -

E = 360°

Sum of Exterior Angles in an Octagon -

E = 360°

Sum of Exterior Angles in a n-sided polygon -

E = 360°

Area Formula for Sector -

θ/360° x πr²

Quadratic Formula -

x =-b ± √(b² - 4ac)/2a

Slope Equation -

y2-y1/x2-x1

Equation of a Line (slope y-intercept form) -

y = mx + b

Equation of a Line (general form) -

Ax + By = C.

A,B, & C are integers. A & B are not both 0.

Equation of a Line (standard form) -

Ax + By = C.

A,B, & C are integers. A & B are not both 0.

Midpoint Formula -

(x₁+x₂)/2, (y₁+y₂)/2

Distance Between Two Points Formula -

d = √[( x₂ - x₁)² + (y₂ - y₁)²]

Difference of Squares Factoring Formula -

a² + b² = (a+b)(a-b)

Perfect Squares Formula (positive version) -

a² + 2ab + b² = (a+b)²

Perfect Squares Formula (negative version) -

a² - 2ab + b² = (a-b)²