The phrase "able to solve it" is correct and usable in written English.
You can use it when discussing someone's capability or skill in resolving a problem or issue.
Example: "With her extensive experience in mathematics, she is able to solve it quickly and efficiently."
Alternatives: "capable of resolving it" or "competent to address it."
The brightest contestants are able to solve it.
He would probably relish the mystery, and not be able to solve it himself.
"It is unlikely you're going to be able to solve it, to be perfectly honest.
You might not be able to solve it yourself and there is help out there.
"It's a shame that they're having this problem and that they haven't been able to solve it," she said.
"If something happened there, nobody would be able to solve it," he said, referring to a war involving Iran.
The current order is simply not able to solve its problems; instead, it hides them, giving them a shiny plasticky new surface, and in a world that dances on the conceptual surface, that's good enough.
Secretary of State Colin L. Powell told reporters Tuesday that North Korea most likely will not be able to solve its economic problems unless it gives up its nuclear program and makes peace with its neighbors.
Don't forget that just because a tool may be able to solve a problem, it doesn't mean that it does so with the flip of a switch; often, onboarding a new software can absorb too much bandwidth and leave you with much bigger problems than what you started with.
War and more war will not be able to solve any of it.
"We shall try, we shall find a solution — a solution that sport is not politics, but sport, in this case, can help to solve the problem and if we are able to solve this problem it could be also a good, let's say step, to solve other problems that you have in this region," he told Abbas.
