Depends on whether you go at this from a mathematical point of view or not. If you do, the answer is 15. Always.
If you look at it from another perspective, something where the term "2(2+3)" does not mean "2*(2+3)", then it can lead to a different solution.
Yet another implicit multiplication vs explicit multiplication problem.
If you value implicit multiplication and explicit multiplication equally, the answer is 15. This will be the answer given by correctly following the order of operations and is the standard accepted mathematical answer.
If you value implicit multiplication over explicit multiplication, the answer is 0.6. This will be the answer given by using shorthand and making assumptions about the equations. Many textbooks and calculators will give the answer as 0.6 because single-line notation takes a long time to correctly write out. People like to use shorthand in these cases.
There is no discussion to be had here. If you want to learn more, do some searching on implicit vs explicit multiplication. The last 3 topics on this just had a bunch of people who didn't understand the order of operations spamming for 10 pages.