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Triangles — MATHS STD 7 — Question

ICSE BoardEnglish MediumSTD 7MATHSTriangles3 Marks
Question
Find the unknown angles in the given figure:
✓

Answer

In the figure,
b = 40° .........(Angles opposite to equal sides)
But a + b + 40° = 180° .........(Angles of a triangle)
⇒ a + 40°+ 40° = 180°
⇒a + 80° = 180°
⇒ a = 180°− 80° = 100°
Hence a = 100°, b = 40°

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