"answer as to whether" is correct and can be used in written English.
You can use it when you want to ask for an answer to a specific yes/no question. For example, "Please answer as to whether you will be able to attend the meeting next week."
"There's no sure answer as to whether France will escape the crisis".
"Then you will have the answer as to whether he is positive or negative".
Transportation and planning experts say there is probably no clear answer as to whether beltways have been good or bad.
For only the cost of the entrance fee, you will get a definitive answer as to whether we believe in bidets.
The State Constitution provides no clear answer as to whether a governor can appoint a second in command if the position is open.
MR. OBAMA: I don't have an answer as to whether the investigation is completed yet, and it wouldn't be appropriate for me to comment on the investigation if I don't -- if it's not yet completed.
Will Shortz has answered the cheating question many times, and his answer as to whether Googling or asking your family for help is cheating always boils down to the same thing.
It's not so clear where these investments belong in a portfolio; in fact, the answer as to whether you should keep them in tax-deferred or taxable accounts depends largely on the vehicles through which the assets are owned.
"So if anybody needs an answer as to whether the Police Department of the City of New York serves all communities," he said, "the Police Department of New York City has proven that with their lives".
So, the answer as to whether strict or casual dress codes are better for business is a complex one: it depends on the industry, the work, and what everyone else is wearing.
And so the lawsuit goes on, Father Mills may be moved again given the most recent publicity, and no one yet has a final answer as to whether anything ever took place between the two men.
