First, move the variable to the left side like this. 6.25x - 9.75x + 30<12
Then you move the constant to the right side and change it sign
6.25x - 9.75x <12 -30.
Collect the like terms
6.25x - 9.75x= -3.5x
-3.5x <12 - 30.
Calculate the difference
12 - 30 = -18
- 3.5x < -18.
Divide both sides of the inequality by -3.5 and flip the inequality sign and you'll get your answer by 36/7