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Learn to identify parallel and perpendicular lines in this Khan Academy geometry lesson for 8th grade.
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Introduction to parallel and perpendicular lines in geometry.
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Proof that perpendicular lines have negative reciprocal slopes.
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Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.
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Khan Academy
Learn how refraction causes light to bend and makes objects appear bent in water.
Free Math Worksheets — Over 100k free practice problems on …
Looking for free math worksheets? You’ve found something even better! That’s because Khan Academy has over 100,000 free practice questions. And they’re even better than traditional math worksheets – more instantaneous, more interactive, and more fun! Just choose your grade level or topic to get access to 100% free practice questions: Early math Kindergarten 1st […]
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What are Streaks and Course Levels? - Khan Academy Help Center
Aug 20, 2024 · Streaks and course levels celebrate your achievements by visually tracking your learning progress across Khan Academy. Leveling up a skill to proficient or better will contribute to your streaks and course levels.
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Uč se zdarma matematiku, programování, hudbu a další předměty. Khan Academy je nezisková organizace, jejímž cílem je poskytovat prvotřídní vzdělání, zdarma, komukoli a kdekoli.