https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-geometry/cc-8th-angles-between-lines/v/angles-formed-by-parallel-lines-and-transversals 2023-05-12T21:01:01.897246564Z Angles, parallel lines, & transversals Parallel lines are lines in the same plane that go in the same direction and never intersect. When a third line, called a transversal, crosses these parallel lines, it creates angles. Some angles are equal, like vertical angles (opposite angles) and corresponding angles (same position at each intersection). Sal Khan video https://cdn.kastatic.org/googleusercontent/Vz_NMEoL9pcokuLJEAFY_U-n9SIzbtc56vA_P8hGFXLXAZEIdmfteizOxfIHqBk4kThnx6aglnEoGdRMahNp4OyW3w Angles, parallel lines, & transversals Parallel lines are lines in the same plane that go in the same direction and never intersect. When a third line, called a transversal, crosses these parallel lines, it creates angles. Some angles are equal, like vertical angles (opposite angles) and corresponding angles (same position at each intersection). https://cdn.kastatic.org/ka-youtube-converted/H-E5rlpCVu4.mp4/H-E5rlpCVu4.mp4 427 Parallel lines and transversals https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-geometry/cc-8th-angles-between-lines/v/identifying-parallel-and-perpendicular-lines 2023-05-12T21:01:01.897246564Z Parallel & perpendicular lines Parallel lines are lines that never intersect, and they form the same angle when they cross another line. Perpendicular lines intersect at a 90-degree angle, forming a square corner. We can identify these lines using angles and symbols in diagrams. Sal Khan video https://cdn.kastatic.org/googleusercontent/PcuXlEbaHxzChubchbUd0bdEVQROnswU9iN3kZmGye3iZfHzIf_3SYhVwwxrzD8EN-ip61hIT490bsiCUZhIeiPq2w Parallel & perpendicular lines Parallel lines are lines that never intersect, and they form the same angle when they cross another line. Perpendicular lines intersect at a 90-degree angle, forming a square corner. We can identify these lines using angles and symbols in diagrams. https://cdn.kastatic.org/ka-youtube-converted/aq_XL6FrmGs.mp4/aq_XL6FrmGs.mp4 215 Parallel lines and transversals https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-geometry/cc-8th-angles-between-lines/v/figuring-out-angles-between-transversal-and-parallel-lines 2023-05-12T21:01:01.897246564Z Missing angles with a transversal When a third line called a transversal crosses two parallel lines, we can find the measures of angles using properties like corresponding angles, vertical angles, and supplementary angles. If we know just one of the angle measurements, these properties help us find all the missing angle measurements. Sal Khan video https://cdn.kastatic.org/googleusercontent/Jc7Hc_hUwIAHvvJpv_xjYjVmNGH5TEE0q90O7tSCCMK6BQ1fOzUe2zl-KCs-2bpIZZ-87m_tAVueoL37Wiy8QB5SOw Missing angles with a transversal When a third line called a transversal crosses two parallel lines, we can find the measures of angles using properties like corresponding angles, vertical angles, and supplementary angles. If we know just one of the angle measurements, these properties help us find all the missing angle measurements. https://cdn.kastatic.org/ka-youtube-converted/2WjGD3LZEWo.mp4/2WjGD3LZEWo.mp4 136 Parallel lines and transversals https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-geometry/cc-8th-angles-between-lines/e/parallel_lines_1 2026-03-24T23:41:07.080866137Z Angle relationships with parallel lines Find missing angles given two parallel lines and a transversal. Marcia Lee exercise https://www.khanacademy.org/math/cc-eighth-grade-math/cc-8th-geometry/cc-8th-angles-between-lines/v/using-algebra-to-find-measures-of-angles-formed-from-transversal 2025-06-10T12:18:12.264638758Z Measures of angles formed by a transversal When parallel lines are crossed by another line called a transversal, special angles are formed. We can find the measures of these angles using algebra and the relationships between the angles, like congruent angles and supplementary angles. Once we solve for the variable, we use that value to figure out the angle measures. Sal Khan video https://cdn.kastatic.org/googleusercontent/jH5ENXnD6D-PN3MBbpChj1DItsL6-IBBlBy4CSWjNhZisvLGEEEuEoyVVhW6tRAfsndWS8O7Q7v4u9lIu_ugTO9D Measures of angles formed by a transversal When parallel lines are crossed by another line called a transversal, special angles are formed. We can find the measures of these angles using algebra and the relationships between the angles, like congruent angles and supplementary angles. Once we solve for the variable, we use that value to figure out the angle measures. https://cdn.kastatic.org/ka-youtube-converted/Ld7Vxb5XV6A.mp4/Ld7Vxb5XV6A.mp4 281 Parallel lines and transversals