A=45, C=15 =>B=(180-(45+15))=120 градусов
Далее по теореме синусов
AC/sin(120) = BC/sin(45)
AC/(√3/2) =2√3/(√2/2)
AC=12/√2=√72 =6√2
A=45, C=15 =>B=(180-(45+15))=120 градусов
Далее по теореме синусов
AC/sin(120) = BC/sin(45)
AC/(√3/2) =2√3/(√2/2)
AC=12/√2=√72 =6√2