a ) Ta có : \(AH^2=BH.HC\)
\(\Rightarrow HC=\frac{AH^2}{BH}=\frac{24^2}{16}=36\left(cm\right)\)
Ta có : \(BC=BH+HC=16+36=52\left(cm\right)\)
\(\Rightarrow AB^2=BC.BH\)
\(AB^2=52.16\)
\(AB=\sqrt{52.16}\)
\(AB=\sqrt{52}.4\)
\(AB=28,8\left(cm\right)\)
\(\Rightarrow AC^2=BC.HC\)
\(AC^2=52.36\)
\(AC=\sqrt{52.36}\)
\(AC=\sqrt{52}.6\)
\(AC=43,3\left(cm\right)\)
b ) Ta có : \(sin\) \(B=\frac{AC}{BC}=\frac{43,3}{52}=0,83\)
\(\Rightarrow\widehat{B}=56^0\)
\(\Rightarrow\widehat{C}=\widehat{A}-\widehat{B}=90^0-56^0=34^0\).
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