Right triangles, areas, slopes, distances and common coordinate-geometry formulas. Use the calculators for your own numbers and the guides for formulas, examples and common questions.
Use the tool that matches the exact problem you need to solve.
Find the hypotenuse of a right triangle from the two perpendicular side lengths.
Solve a right triangle from two side lengths and find the hypotenuse, angles, area and perimeter.
Calculate triangle area using a base and perpendicular height.
Find the slope of the line through two coordinate points.
Calculate straight-line distance between two points on a 2D coordinate plane.
Find the midpoint between two points on a coordinate plane.
Calculate circumference and area from a circle radius.
Calculate area, perimeter and diagonal of a rectangle from length and width.
Solve a quadratic equation in the form ax² + bx + c = 0 and identify real or complex roots.
Calculate cone volume, slant height and total surface area from radius and vertical height.
Calculate the volume and total surface area of a right circular cylinder.
Calculate the volume and surface area of a sphere from its radius.
Three long-tail answers that explain formulas and common scenarios behind this calculator cluster.
Learn how to use a²+b²=c² to find the hypotenuse or a missing leg of a right triangle.
Read guide →Geometry & TrianglesLearn the base-times-height formula for triangle area and how to use perpendicular height correctly.
Read guide →Geometry & TrianglesLearn the slope formula from two coordinate points and recognize positive, negative, zero and undefined slope.
Read guide →Right triangles, areas, slopes, distances and common coordinate-geometry formulas. The pages in this cluster are intentionally connected: calculator pages handle the arithmetic, while the guides answer informational searches, show worked examples and explain how to interpret the result.
Use the examples as reference points, then open a calculator and substitute your own values. For decisions involving contracts, taxes, health, payroll rules, construction requirements or other high-stakes details, verify the real-world assumptions with an appropriate authoritative source.
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