Num8ers complete reference
Complete K-12 Math Formula Guide
Search all 440 formulas across arithmetic, algebra, geometry, trigonometry, statistics, probability, financial math, precalculus, matrices, vectors, logic, and AP or IB extensions.
How to use this formula guide
Search by formula name, topic, or keyword.
Filter by a topic pill to narrow the list.
Read the expression, definition, and variables.
Use the mini calculator for common formulas.
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440 of 440 formulas shown.
Math Formula FAQs
Does this K-12 math formula page include all 440 formulas?
Yes. It includes all 440 formulas from the uploaded K-12 math checklist, grouped by category with formulas, definitions, and variable explanations.
How should students use this math formula guide?
Search a topic or formula name, read the definition and variables, then substitute the values carefully.
What is the formula for percent of a number?
Percent of a number is p percent of N = (p/100)N.
What is the slope formula?
Slope is m = (y2 - y1) / (x2 - x1).
What is the equation of a line?
A common line form is y = mx + b, where m is slope and b is the y-intercept.
What is the quadratic formula?
For ax^2 + bx + c = 0, x = (-b plus or minus sqrt(b^2 - 4ac)) / 2a.
What is the Pythagorean theorem?
For a right triangle, a^2 + b^2 = c^2.
What is the area formula for a triangle?
Triangle area is A = 1/2 bh.
What is the circumference formula?
Circle circumference is C = 2 pi r or C = pi d.
What is the area formula for a circle?
Circle area is A = pi r^2.
What is the distance formula?
Distance between two points is d = sqrt((x2 - x1)^2 + (y2 - y1)^2).
What is the midpoint formula?
Midpoint is ((x1 + x2)/2, (y1 + y2)/2).
What is the mean formula?
Mean is x-bar = sum of values divided by the number of values.
What is the probability formula?
Probability is favorable outcomes divided by total outcomes.
What is the compound interest formula?
Compound interest is A = P(1 + r/n)^(nt).
What is the sine ratio?
Sine is opposite side divided by hypotenuse.
What is the law of cosines?
One form is c^2 = a^2 + b^2 - 2ab cos C.
What is a logarithm rule students use often?
A common rule is log_b(MN) = log_b M + log_b N.
What is the derivative power rule?
The power rule is d/dx x^n = nx^(n-1).
What is the basic integral power rule?
For n not equal to -1, integral x^n dx = x^(n+1)/(n+1) + C.