In △ ABC, ∠ C = 90 ° 4B2 + 3c2 = 43bc, can we find the degree of ∠ a? If you can, work it out. If you can't, explain the reason

Energy, ∵ 4B2 + 3c2 = 43bc, ∵ 4b2-43bc + 3c2 = 0, ∵ (2b − & nbsp; 3C) 2 = 0, ∵ 2B = 3C, ∵ BC = cosa = 32, ∵ a = 30 °

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