Distance in the Coordinate Plane
Distance =
if you’re measuring the distance between the points (
x1,
y1) and (
x2,
y2).
Distance in the Coordinate Space Distance
Distance =
if you’re measuring the distance between the points (
x1,
y1,
z1) and (
x2,
y2,
z2).
Midpoint between Two Points
Midpoint = (
, 
), where the endpoints of a line segment are (
x1,
y1) and (
x2,
y2).
Point-Slope Form of the Equation of a Line
y – y1 = m(x – x1), where m is the slope of the line, and (x1, y1) is a point on the line.
Slope-Intercept Form of the Equation of a Line
y = mx + b, where m is the slope of the line, and b is the y-intercept of the line. Both m and b are constants.
Slope of a Line
Slope =
, where two points on the line are (
x1,
y1) and (
x2,
y2).
Standard Form of the Equation of a Circle
(x – h)2 + (y – k)2 = r2, where (h, k) is the center of the circle, and r is the radius. When centered at the origin, the equation simplifies to x2 + y2 = r2.
Standard Form of the Equation of a Parabola
y = a(x – h)2 + k, where a, h, and k are constants.
