https://www.khanacademy.org/math/cc-fourth-grade-math/imp-geometry-2/imp-measuring-angles/v/constructing-angles 2021-06-30T20:49:26Z Constructing angles Sal uses a protractor to create 10° and 155° angles. Sal Khan video https://cdn.kastatic.org/googleusercontent/vwVwXCac9YgvLk2XcKJT3VMMic41xJrnL_cSRhc7GfLJMxBO7vEbB34DX_PFBiUjWTi0-B7_cDHbykrQLYrmEYY Constructing angles Sal uses a protractor to create 10° and 155° angles. https://cdn.kastatic.org/ka-youtube-converted/QmfoIvgIVlE.mp4/QmfoIvgIVlE.mp4 161 Geometrical construction https://www.khanacademy.org/math/cc-fourth-grade-math/plane-figures/imp-angle-introduction/v/drawing-acute-right-and-obtuse-angles 2021-06-30T20:49:31Z Drawing acute, right and obtuse angles Learn how to draw acute, right, and obtuse angles with given points. Sal Khan video https://cdn.kastatic.org/googleusercontent/o2TonhaOTksJDG2GYnogr8_KSb2kBdKglPMAkrDCX12basBnHp8r8hhgLbT24-ZKl_tVnFAPZ-2u15lmg-6THbpd Drawing acute, right and obtuse angles Learn how to draw acute, right, and obtuse angles with given points. https://cdn.kastatic.org/ka-youtube-converted/4ZyTVTGVPgE.mp4/4ZyTVTGVPgE.mp4 160 Geometrical construction https://www.khanacademy.org/math/cambridge-o-level-mathematics-4024/x3f4c73d082a798eb:geometry/x3f4c73d082a798eb:geometrical-construction/v/construct-a-triangle-two-sides-angle-given 2026-03-10T04:30:37.966653692Z Construct a triangle: Two sides & angle given Created by Khan Academy Khan Academy Pakistan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Construct a triangle: Two sides & angle given Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/1FNgzScGrBo.mp4/1FNgzScGrBo.mp4 221 Geometrical construction https://www.khanacademy.org/math/cambridge-o-level-mathematics-4024/x3f4c73d082a798eb:geometry/x3f4c73d082a798eb:geometrical-construction/v/construction-with-two-angles-sides-given 2026-03-10T04:30:37.966653692Z Construction with two angles & sides given Created by Khan Academy Khan Academy Pakistan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Construction with two angles & sides given Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/BTxiZLdi5SY.mp4/BTxiZLdi5SY.mp4 326 Geometrical construction https://www.khanacademy.org/math/cambridge-o-level-mathematics-4024/x3f4c73d082a798eb:geometry/x3f4c73d082a798eb:geometrical-construction/v/construct-a-triangle-with-hypotenuse-and-side-are-given 2026-03-10T04:30:37.966653692Z Construct a triangle with hypotenuse and side are given Created by Khan Academy Khan Academy Pakistan video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Construct a triangle with hypotenuse and side are given Created by Khan Academy https://cdn.kastatic.org/ka-youtube-converted/0uOprtxOkx8.mp4/0uOprtxOkx8.mp4 410 Geometrical construction https://www.khanacademy.org/math/cc-seventh-grade-math/cc-7th-geometry/cc-7th-constructing-geometric-shapes/v/constructing-triangles-with-constraints 2021-06-30T20:49:37Z Construct a triangle with constraints Here's a challenge: in this problem we are given constraints and asked to construct a triangle. It can be done! You'll learn about degenerate triangles, too. Sal Khan video https://cdn.kastatic.org/googleusercontent/8QJGN2mqMMqvYB8ggWc1XozqdQaRPF-AHhMHiAkYM_hDxwOJ8p5DYL3UVFenVO639rtOnY9WDn0xyfYpaNF5XjOF Construct a triangle with constraints Here's a challenge: in this problem we are given constraints and asked to construct a triangle. It can be done! You'll learn about degenerate triangles, too. https://cdn.kastatic.org/ka-youtube-converted/E78ji1uBtSA.mp4/E78ji1uBtSA.mp4 239 Geometrical construction https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-geometry-topic/x0267d782:cc-6th-nets-of-3d-figures/v/surface-area-of-a-box-using-nets 2023-09-21T21:49:35.177342261Z Surface area of a box using nets Discover the surface area of a cereal box by visualizing a net. Cut and flatten the box to create a 2D shape. Measure the dimensions, calculate the area of each section, and add them up for the total surface area. Fun and practical! video https://cdn.kastatic.org/googleusercontent/ZCdwTudJg6e6n-P2gsaUborP4izvMsGo71pvEVlX9dNYWcLXcP7VHkWpn2grt4TUP1KoJLQP9NswyHBuBLSFTBw Surface area of a box using nets Discover the surface area of a cereal box by visualizing a net. Cut and flatten the box to create a 2D shape. Measure the dimensions, calculate the area of each section, and add them up for the total surface area. Fun and practical! https://cdn.kastatic.org/ka-youtube-converted/vl1uMOYFyf4.mp4/vl1uMOYFyf4.mp4 284 Geometrical construction https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-geometry-topic/x0267d782:cc-6th-nets-of-3d-figures/e/surface-area 2026-04-07T23:55:07.30621384Z Surface area using nets Practice using the net of a 3D figure to find surface area. Matthew Evans exercise https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-geometry-topic/cc-6th-surface-area/a/3d-figures-faq 2024-05-09T14:45:00.769995577Z 3D figures FAQ Frequently asked questions about 3D figures article