Perpendicular planes
Perpendicular planes are planes that intersect at a right angle.
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Perpendicular planes and lines
If one plane contains a line that is perpendicular to another plane, these two planes are perpendicular to each other.
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Line l in plane n is perpendicular to plane m, so planes n and m are perpendicular planes.
If a line is perpendicular to a plane, many perpendicular planes can be constructed through this line.
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Planes n, p, and q contain line l, which is perpendicular to plane m, so planes n, p, and q are also perpendicular to plane m.
If a line is perpendicular to a plane, any lines in the plane that intersect it are perpendicular to it.
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Line l perpendicular to plane m. Lines 1, 2, and 3 in plane m intersect line l, so they are also perpendicular to line l.