Q1
Two triangles are similar if their:
Acorresponding angles are equal
Ball sides are equal
Conly one angle matches
Dperimeters are equal
CBSEClass 10 (CBSE)MathematicsCh 6 · Topic 1
Criteria for Similarity of Triangles
Learning the conditions under which two triangles are similar.
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The AA criterion is particularly powerful and efficient, since if just two angles of one triangle equal two angles of another, the third angles must also be equal (since all triangle angles sum to 180°), guaranteeing similarity without needing to check any side lengths at all. Similar triangles have countless applications, from indirect height measurement (like finding a tall building's height using its shadow and a similar smaller object's shadow) to map-making and scale models.
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CBSE class 10 criteria for similarity of triangles
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• Similar triangles have equal corresponding angles and proportional corresponding sides.
• Similarity criteria: AA (two angles equal), SSS (sides proportional), SAS (two sides proportional + included angle equal).
• AA is efficient since equal third angles are guaranteed by the angle sum property.
• Similar triangles are used in indirect height measurement, mapping, and scale models.