C-09-Q071mediumsingle_mcqIn right △ABC\triangle ABC△ABC with ∠C=90∘\angle C = 90^\circ∠C=90∘, AB=29AB = 29AB=29, BC=21BC = 21BC=21, ∠ABC=θ\angle ABC = \theta∠ABC=θ. Then AC=?AC = ?AC=?a181818b202020c222222d242424ব্যাখ্যাWith ∠C=90∘\angle C = 90^\circ∠C=90∘, ABABAB is the hypotenuse. By Pythagoras, AC=AB2−BC2=292−212=841−441=400=20AC = \sqrt{AB^2 - BC^2} = \sqrt{29^2 - 21^2} = \sqrt{841 - 441} = \sqrt{400} = 20AC=AB2−BC2=292−212=841−441=400=20.