segitiga abc besar sudut a 30°, B 45° dan sisi b 10cm. brp pjg sisi a?

Aturan sinus

a/sin A = b/sin B
a = (b. sin A)/(sin B)
a = (10 x sin 30) / (sin 45)
a = (10 x 1/2) /(1/2 √2)
a = 10 /√2
a=  5 √2