Math: Facts & Formulas Flashcards
to learn formulas for determining area and volume
Area of a Regular Polygon
nx/2 (side length times apothem)/2
(number of sides x length of one side x apothem)/2
Area of a Regular Polygon
diameter
d = 2r (radius)
2 x radius =
diameter
circumference
2 x π x radius
2 x π x r
circumference
How to get radius if you know circumference
C/2π = r
Area of a Parallelogram
base x height
Area of a Triangle
(base x height)/2 or 1/2(base x height)
(base x height)/2 or 1/2(base x height)
Area of a Triangle
Area of a Square
side squared
side times side
Area of a square
Area of a Trapezoid
1/2 (Top base + bottom base) x height
1/2 (Top base + bottom base) x height
Area of a Trapezoid
Another way to say 1/2 (anything)
Divide (anything) by 2
Area of a Rectangle
Length x width
Length x width
Area of a Rectangle
The area is always written by the measurement__________
squared
Area of an Ellipse
π x radius of major axis x radius of minor axis
π x radius of major axis x radius of minor axis
Area of an Ellipse
π
3.14 or 22/7
3.14 or 22/7
π
Volume of a cube or rectangular box
length x width x height
length x width x height
Volume of a cube or rectangular box
Volume of a sphere
V = 4/3π(radius cubed)
V = 4/3π(radius cubed)
Volume of a sphere
Volume of a cone
V = [π(radius squared)h)]/3
V = [π(radius squared)h)]/3
Volume of a cone
Volume of a Pyramid
Volume = (Area of the Base x Height)/3
Volume = 1/3 x Area of the Base x Height
Volume of a Pyramid
Volume of a Rectangular Prism
(V) = l × w × h
(V) = l × w × h
Volume of a Rectangular Prism
Volume of a Cylinder
π × cylinder radius² × cylinder height
π × cylinder radius² × cylinder height
Volume of a Cylinder
The volume of an object is always expressed as the measurement
______________
Cubed
How do you get the Surface Area of a Pyramid?
- Compute the area of the base
- Compute the perimeter of the base
- Identify the Slat Height (no the pyramid height.)
- Use this formula:
SA = Base Area + Half of (Perimeter of the base x Slant Length)
4.1
What are the rules for rounding decimals?
- Identify the place value to be rounded.
- Look to the digit to the RIGHT of the number being rounded.
- If it is 4 or less then change it and all the numbers after it to 0.
- If it is 5 or more, increase the number being rounded by 1 and then change all the numbers after it to 0.
?How do you round 362.715 to the nearest tenth and to the nearest tens?