Tolong ya kak…besok mau di kumpultolong pakai caranya:v​

20)L segitiga=1/2×a×t

=1/2×20×12

=240/2

=120 cm²

L persegi panjang=p×l

=20×10

=200 cm²

L gabungan=L segitiga+L persegi panjang

=120 cm²+200 cm²

=320 cm² (B)

21)L=a×t

=28×12

=336 cm²(C)

22)K=2×(p+l)

=2×(28+13)

=2×41

=82 cm(B)

23)K=2×π×r

=2×22/7×28

=1232/7

=176 cm(A)

24)L=3/4×π×r²

=3/4×22/7×21×21

=63/4×462/7

=29106/28

=1039,5 cm²(B)

Semoga membantu ya kak…
Jadikan ter-brainly…
Thanks…