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Kris5
how do i subtract 2 radical 15 - 5 radical 2?
depends what you are doing. You can write it as \[ 2\sqrt{15}-5\sqrt{2} \] which is as simple as you can get it. However, you could use a calculator and change it to an (approximate) decimal number.
Ohh alright, then I'm probably doing something wrong on my math problem :/