How to find the measure of a missing angle

Which equation and solution can be used to solve this problem? thirteen less than a number is sixteen. 13-n=16: add 13 to both sides. the answer is 29. n+13=16: subtract 13 from both sides. the answer is 3. n+16=13 subtract 13 from both sides. the answer is 3. n-13=16: add 13 to both sides. the answer is 29.

Determine whether the set of whole numbers is closed under addition. explain why the set is or is not closed. give an example.

If f(x) = 4x – 3 and g(x) = 8x + 2, find each function value a. f[g(3)] b. g[f(5)] c. g{f[g(-4)]}