Answer:
This expression is not factorable with rational numbers.
Explanation:
The way factoring works, you just want to get it to its smallest form possible. To do that you would divide the entire problem by the Least Common Multiple.
This problem does not have a least common multiple. The LCM of 16 and 64 is 16 but x^2 does not have a number in front. 16k and 64 can be factored but in order to factor the entire problem, x^2 would need to have a number in front that made it divisible by a common multiple of 16 and 64.
Say if the problem was 2x^2+16k+64, you could divide the entire problem by 2. Your answer would be:
2(x^2+8k+32)
It is important to note that when you are factoring, never divide any exponents.
The way to check your work when factoring is to distribute the number outside of the parentheses. So in the example I just gave, you'd multiply everything in the parentheses, except the exponent, by 2. Which will give you the original 2x^2+16k+64.
Whatever number you factor out and end up putting outside your parentheses, should multiply back into the parentheses to give you the original problem. If it doesn't, then the factoring was done incorrectly.
Your answer should include parentheses.