Is -15 a whole number, integer, or a rational?

Integer and rational

Explanation:

The set of whole numbers is defined to be {0, 1, 2, 3, } so it's composed of numbers that don't have any decimal or fractional components. We start at 0 with this set. We don't include negative numbers here.

Integers are basically the same as whole numbers, but now we include negative values {..., -3, -2, -1, 0, 1, 2, 3, ...} so we see that -15 is in the set of integers.

The value -15 is also a rational number because -15 = -15/1, meaning we can write -15 as a fraction of integers. Any rational number is of the form a/b with a,b being integers and b is nonzero.

not only in mathematics, scientific proof also are required in the other field of science. also maths proofs are of particular structure, containing steps and logics. so proving is like doing science, it is science. that's why it is important to prove. 

an inaccurate proof leads to errors, or stating results that are not accurate.  which wil mess the probelm up you dont want this