Answer:
Step-by-step explanation:
3x-7=23
<=> 3x = 23 + 7
<=> 3x = 30
<=> X = 30 ÷ 3
<=> X = 10
Answer:
sorry I can't help you this is hard for me sorry. :(
Step-by-step explanation:
Answer:
1. The tetrahedron has 4 vertices, 6 edges and 4 faces. Then V-E+F=4-6+4=2
2. The cube has 8 vertices, 12 edges and 6 faces. Then V-E+F=8-12+6=2
3. The octahedron has 6 vertices, 12 edges and 8 faces. Then V-E+F=6-12+8=2
4. The icosahedron has 12 vertices, 30 edges and 20 faces. Then V-E+F=12-30+20=2
5. The dodecahedron has 20 vertices, 30 edges and 12 faces. Then V-E+F=20-30+12=2.
