Area = p × radius2; p is approximately equal to 3.14.
PERIMETER of a:
Perimeter = 4 × side
Perimeter = 2 × length + 2 × width
Perimeter = side1 + side2 + side3
CIRCUMFERENCE of a circle
Circumference = p × diameter; p is approximately equal to 3.14.
VOLUME of a:
Volume = edge3
Volume = length × width × height
Volume = 1/3 × (base edge)2 × height
Volume = p × radius2 × height; p is approximately equal to 3.14.
Volume = 1/3 × p × radius2 × height; p is approximately equal to 3.14.
distance between points = ; (x1, y1) and (x2, y2) are two points in a plane.slope of a line = ; (x1, y1) and (x2, y2) are two points on the line.
a2 + b2 = c2; a and b are legs and c the hypotenuse of a right triangle.
MEASURES OF CENTRAL TENDENCY
mean = , where the x‘s are the values for which a mean is desired, and n is the total number of values for x.median = the middle value of an odd number of ordered scores, and halfway between the two middle values of an even number of ordered scores.