No 3 dan 4 gimana caranya

4. keliling : s+s+s
13+13+10 = 36cm
luas :
[tex] \frac{1}{2} \times a \times t \\ \frac{1}{2} \times 10 \times 12 \\ 5 \times 12 \\ 60 {cm}^{2} [/tex]

Nomor 3
K=s1+s2+s3
=10+15+13
=38cm
L=1/2.a.t
=1/2.10.10
=100/2
=50cm²
Nomor 4
K=s1+s2+s3
=10+13+13
=36cm
s2 itu sama aja kya s3
L=1/2.a.t
=1/2.10.12
=1/2.120
=60cm²