tolong dibantu nomor 7 yah poin banyak

a.
→ Luas :
= a x t / 2
= (16 + 5) x 12 / 2
= 21 x 6
= 126cm²

→ Keliling :
= 20cm + 13cm + 16cm + 5cm
= 54cm

b.
→ Luas :
= a x t / 2
= 9 x 8 / 2
= 9 x 4
= 36cm²

→ Keliling :
= 9 + 10 + 17
= 36cm

a. Luas segitiga
= 1/2 x a x t
= 1/2 x AB x DC
= 1/2 x 21 x 12
= 126 cm²

Keliling segitiga
= AD + DB + BC + CA
= 16 + 5 + 13 + 20
= 54 cm

b. Luas segitiga
= L PSR - L QSR
= 1/2 x a x t - 1/2 x a x t
= 1/2 x PS x SR - 1/2 x QS X SR
= 1/2 x 15 x 8 - 1/2 x 6 x 8
= 60 - 24
= 36 cm²

Keliling segitiga
= PQ + QR + RP
= 9 + 10 + 17
= 36 cm