In theis diagram AB=AC angle A = 40 degree and BD is perpendicular to AC at D. how many degrees are there in angle DBC?
In theis diagram AB=AC angle A = 40 degree and BD is perpendicular to AC at D. how many degrees are there in angle DBC? Correct Answer 20 degree
△ABC এ AB = AC,∠B = ∠C∴∠A + ∠B + ∠C = 180∘⇒∠B + ∠C = 180∘ - 40∘⇒∠B + ∠C = 140∘⇒2∠B = 140∘∴∠B = 70∘ = ∠CAgain, △ABD এ ∠ADB = 90∘∠A = 40∘∴∠DBA = 180∘ - 90∘ - 40∘ = 50∘ ∴∠DBC = ∠ABC - ∠DBA = 70∘ - 50∘ = 20∘
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Feb 20, 2025