To begin with, we need to rationalize the denomenator. To do so, we multiply that by 3+2√2. (this is an excellent website for rationalizing the denominator: https://www.chilimath.com/lessons/intermediate-algebra/rationalizing-the-denominator/)
Anyways, multiply the top and bottom by 3+2√2. This will give you 88+54√2.
This involves casework. So, let's first see how many options there are for 5 digits:
This is basically 10 to the power of 5 (ten numbers from 0-9, and you can repeat, so 10(10)(10)(10)(10), which is 10^5), which is 100,000
(If you don't understand combinations, here is a link you could refer to: https://www.mathsisfun.com/combinatorics/combinations-permutations.html)
Same thing for 6, but 10^6, and you would get 1,000,000. Add those together, and you have 1,100,000.
(Not sure if you acctually read my explanation, or read this , but here is a trickier practice problem for you (refer to website linked above if confused). Use the same problem that you stated above, BUT, instead, you can't repeat digits. (maybe not that much trickier, but you should try it.))