How to Multiply Matrices Step by Step
Learn the rules for multiplying matrices, check the sizes, work a 2 by 2 example, and see why the order matters. Includes addition, determinant, and inverse.
Blogs
Plain-English guides to the maths, money, school, and health topics behind our calculators, with worked examples you can follow.
How Body Fat Percentage Is Estimated From Measurements
See how the US Navy tape measure method and the BMI method estimate body fat, how to measure correctly, the standard ranges, and their limits.
A1C to Average Glucose (eAG): How the Conversion Works
Understand how A1C converts to estimated average glucose in mg/dL and mmol/L, see the formula and a conversion chart, and why the numbers may differ.
What Is a Limit in Calculus? A Plain-English Guide
Understand limits in calculus: what they mean, how to find them with substitution, factoring, and L’Hôpital’s Rule, and when a limit does not exist.
How to Factor Polynomials: Methods With Examples
Learn how to factor polynomials step by step: common factors, trinomials, difference of squares, cubes, grouping, and rational roots, with worked examples.
What Score Do You Need on Your Final Exam?
Use one formula to find the final exam score you need for your target grade, see how the exam weight changes the answer, and what to do if it is over 100%.