Cracking exam and getting good rank are two different things if you just want to clear the cutoff then only you can do it without doing mathematics however if you are interested in getting a good rank and getting a good college then you must get good score in mathematics also because all three part combined together to the rank.

It must be noted that you are applying for architecture and they are having mathematics exam so there must be some reason behind it so if you want to good in that particular field then mathematics is required thing as much as need in the exam therefor you need to overcome the fear of mathematics and don't just run away from it.

You can improve your mathematics by regularly solving the problems in the beginning you may feel the problems are tough but as you practice not a lot the subject will become easier for you