tolong bantu aku dalam mengerjakan soal mtk

no.27
kelilingΔ=pr+rq+pq
48 cm=x+15+15
48 cm=x+30
x=48-30
x=18

LuasΔ=1/2 ×alas×tinggi
=108cm
no.28
keliling PP=2.p+2.l
36=2p+2.8
36=2p +16
2p=36-16
2p=20
p=20/2
p=10

Luas PP=p.l
=10.8
=80cm²(b)
no 29
Luas P1=s²
=7²
=49 cm²
Luas P2=s²
=14²
=196 cm²
Perbandingan=P1:P2
=49:196
=1:4(c)
no 30
Keliling jajargenjang=2.a+2.b
36=2.8+2.x
36=16+2x
2x=36-16
2x=20
x. =20/2
x =10cm(a)