Tolong kasih tau ya No 4 sama 5

4).L1 = 1/2 ( a + b. ) t
= 1/2 (21 +42) 21
= 1/2 (63) 21
= 661,5cm^2
L2= 1/2 π r^2
= 1/2 x 22/7 x 21/2 x 21/2
= 173,25
Luas total= 661,5 -173,25 =488,28cm^2

5).L1 =1/2 x a x t
= 1/2 x15 x5 =37,5 cm^2
L2=1/2 x (a + b) t
=1/2 x (15 + 21) 7
= 1/2(36)x 7
= 126cm^2
Luas total =37,5 + 126 =163,5 cm^2