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In Fig., OP, OQ, OR and OS are four rays, prove that:∠POQ + ∠QOR + ∠SOR + ∠POS = 360° |
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Answer» Given that, OP, OQ, OR and OS are four rays You need to produce any of the rays OP, OQ, OR and OS backwards to a point T so that TOQ is a line. Ray OP stands on line TOQ ∠TOP + ∠POQ = 180°(Linear pair) (i) Similarly, ∠TOS + ∠SOQ =180°(ii) ∠TOS + ∠SOR + ∠OQR = 180°(iii) Adding (i) and (iii), we get ∠TOP + ∠POQ + ∠TOS + ∠SOR + ∠QOR = 360° ∠TOP + ∠TOS = ∠POS Therefore, ∠POQ + ∠QOR + ∠SOR +∠POS = 360°. |
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