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Created by experts, Khan Academy’s library of trusted, standards-aligned practice and lessons covers math K-12 through early college, grammar, science, history, AP®, SAT®, and more.

Geometry (all content) 17 units · 180 skills Unit 1 Lines Unit 2 Angles Unit 3 Shapes

This unit introduces you to the foundational geometry and trigonometry skills you'll need on the SAT Math test, starting with more basic examples. We suggest leveling up each skill with …

Geometry (all content) 17 units · 180 skills Unit 1 Lines Unit 2 Angles Unit 3 Shapes

Learn high school geometry—transformations, congruence, similarity, trigonometry, analytic geometry, and more (aligned with Common Core standards).

Early humans needed ways to count, so they created basic numbers. Symbols like "+" and "=" were invented later to make math easier. Zero was a big breakthrough because it helped with …

4th grade math 14 units · 154 skills Unit 1 Place value Unit 2 Addition, subtraction, and estimation Unit 3 Multiply by 1-digit numbers

Geometric shapes are all around us. The world is built with them. In this series of tutorials and exercises you'll become familiar with Euclidean geometry and terms like scale drawings, parts …

Learn fifth grade math—arithmetic with fractions and decimals, volume, unit conversion, graphing points, and more. This course is aligned with Common Core standards.