Answer:
[tex]AB^{2} =AD^{2} +BD^{2}[/tex]
[tex]AB^{2} =(7.5)^{2} +(4.9)^{2}[/tex]
[tex]AB=\sqrt{80.26}[/tex]
[tex]=8.96[/tex]
ΔABC tan C=AB/BC
⇒ tan 55.8= 8.96/BC ⇒BC= 8.96/tan 55.8
BC=x= 6.09
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Hope it helps...
Have a great day!!
