A rational number is a number that can be expressed as the relationship between two integers. Fractions and decimals will either repeat or end. An example is 5. Maybe 7. 53573 is an example as well. So is 5/1, because 5 and 1 are both integers. so is 7.5, because 7 and 5 are both integers, and it ends (the numbers after the decimal doesn't keep going). Your answer is 7.8, because it ends.
C = 2πr
17 = 2(3.14)(r)
17 = 2(3.14r)
17 = 6.28r
6.28 6.28
2.71 ≈ r
You multiply like terms first, which means -2/3x*-x. It becomes 2/3x*3y. The coefficient of x is 2/3. The coefficient of y is 3. You can’t combine them because they are not like terms with the variables.
Your identity says ...
... sum of cubes = (sum)³ -3(product)(sum)
... = 4³ -3·1·4
... = 64 -12 = 52
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The two numbers are 2±√3, and the sum of their cubes is indeed 52.
B. A hexagonal prism would have every side be a hexagon or a triangle.
