[tex]36-b ^ { 2 } -c ^ { 2 } +2bc\\= 36-\left(b^{2}+c^{2}-2bc\right) \\= 6^{2}-\left(b-c\right)^{2} \\=\boxed{ \left(6-b+c\right)\left(6+b-c\right) }[/tex]
Hope it helps ⚜