There are lots of answers for m and a (when they’re positive whole numbers).

For example, m=2, a=58, because

8×3+3×58-98×2=24+174-196=198-196=2;

m=5, a=156, because

8×3+3×156-98×5=24+468-490=492-490=2;

m=8, a=254, because

8×3+3×254-98×8=24+762-784=786-784=2.

The next value of m is 3 more than the last (8+3=11). To find a, use the formula:

(98m-22)/3. When m=11, a=352. a increases by 98 each time.

I hope this is what your question is looking for. I don’t know why you should subtract 5, but if you do you will start with m=1 and a=27, followed by m=4 (an increase of 3) and a=125 (an increase of 98).