1.sebuah kayu berlubang tampak,seperti gambar di samping.luas parmukaan kayu adalah.....cm2

Lp.total = 2(pl + pt + lt)
Lp.total = 2(8.10 + 8.3 + 10.3)
Lp.total = 2.134
Lp.total = 268 cm"

Lp.lubang = 2(pl + pt + lt)
Lp.lubang = 2(3.10 + 3.3 + 10.3)
Lp.lubanh = 2.69
Lp.lubang = 138 cm"

Lp kayu = Lp.total - Lp.lubang
Lp kayu = 268 cm" - 138 cm"
Lp kayu = 130 cm"

Semoga membantu dan semoga bermanfaat...