I don’t know if you were asking for that cause my english is not that good but i hope that i helped you
The given equality hold true when x = 2.
Put x = 2 in inequality.
2(2) + 3 = 4+3 = 7 = R.H.S.
For x = 4 and 6, L.H.S(2x+3) is greater than 7.
Hence for x = 2, 4 and 6, the above inequality holds true.
Hope this helps!
The rate of change for function A is 2. It would originally be 2 over one but you can just simplify it down to 2. The rate of change for function B is 3. Which would also originally be 3 over 1.