Jawapan

2016-09-16T13:56:17+08:00
Formula : 1/2(a+b)c .................
2016-09-16T15:11:18+08:00
Guna kaedah persamaan linear
1/2 x 10 x (15+p) = 135
1/1 x 5 x (15+p)=135
1/1 x (75 + 5p ) = 135
(75 + 5p)=135
5p = 135-75
5p=60
p=60/5
p=12#