Answer: 51
Step-by-step explanation:
2 octagons have 16 sides because an octagon has eight sides. So, 8x2=16.
4 pentagons have 20 sides because a pentagon has 5 sides. So, 4x5=20.
5 triangles have 15 sides because a triangle has 3 sides. So, 5x3=15.
In all, 16+20+15= 51
