Octahedron has 8 faces, icosahedron has 20 faces. Therefore the answer is dodecahedron, it has 12 faces.
Step-by-step explanation:
3×3 = 9, so it's greater than 3
3×4/3 = 4, so it's greater than 3
3×5/5 = 3, so it's equal to 3
3x4/9 = 4/3, so it's less than 3
3x5/6 = 5/2, so it's less than 3
A prime number means that the number is only divisible by one and itself.
14 is a multiple of 2 and 7, so 14 wouldn't be it.
21 is a multiple of 3 and 7, so 21 wouldn't be it.
33 is a multiple of 3 and 11, so 33 wouldn't be it.
13 is only divisible by itself because no number can be multiplied to get 13.
So the correct answer is : 13 is the prime number.
Expand 8(5-r)/5=-2r as indicated: 40 - 8r
----------- = - 2r
5
Multiply both sides by 5, obtaining 40 - 8r = - 10r
Combine like terms: 40 = - 2r
Divide both sides by -2: -20 = r
The solution to 8(5-r)/5=-2r is -20. Verify this by subbing -20 for r in the given equation.
