5. The diagram shows triangle \(A B C\), with \(A B = x \mathrm {~cm} , A C = ( x + 2 ) \mathrm { cm } , B C = 2 \sqrt { 7 } \mathrm {~cm}\) and angle \(C A B = 60 ^ { \circ }\).
i. Find the value of \(x\).
ii. Find the area of triangle \(A B C\), giving your answer in an exact form as simply as possible.