luas permukaan bagun gabungan

luas permukaan balok
= 2 × p × L + L × t + p × t
= 2 × 13 × 8 + 8 × 8 + 13 × 8
= 2 × 104 + 64 + 104
= 2 × 272
= 544 cm2

luas permukaan Limas
= 3 × L segitiga + La
= 3 × 1/2 × a × t + p × l
= 3 × 1/2 × 8 × 9 + 13 × 8
= 3 × 36 + 104
= 108 + 104
= 112 cm2

Lp gabungan

= 544 + 112
= 656 cm2

semoga bermanfaat