Respuesta :

anchitthawi
find a first
sin 45° = 1/√2 = a/7√2
so a= 7

then find c
tan 30° = √3/3 = a/c
√3/3 = 7/c
so c= 7*3/√3 = 21/√3 = 21√3/3 = 7√3