Tolong dijawab ya kak

Perhatikan ∆PSQ
QS^2 = PQ^2 + SP^2 - 2 . PQ . SP cos 45°
QS^2 = (4√2)^2 + 4^2 - 2 . 4√2 . 4 . 1/2 √2
QS^2 = 32 + 16 - 32
QS^2 = 16
QS = √16 = 4

Perhatikan ∆QRS
QS/(sin R) = RS/(sin Q)
4/(sin 30°) = RS/(sin 60°)
4/(1/2) = RS/(1/2 √3)
4/1 = RS/(√3)
RS = 4√3
segitiga siku-siku
Luas ∆QRS = 1/2 x QS x SR = 1/2 x 4 x 4√3 = 8√3