To solve for b, we need to get b on one side of the equation and all the other numbers on the other side. To do this, we can start by adding 3 1/2 to both sides of the equation:
-3 1/2 + 3 1/2 = 1 1/4b + 3 1/2
This simplifies to:
0 = 1 1/4b + 3 1/2
Now we can subtract 3 1/2 from both sides of the equation:
0 - 3 1/2 = 1 1/4b
This gives us:
-3 1/2 = 1 1/4b
To solve for b, we can divide both sides of the equation by 1 1/4. To do this, we need to convert the mixed number to an improper fraction:
-14/2 = 1 1/4b
Now we can divide both sides of the equation by 1 1/4:
-14/2 ÷ 1 1/4 = b
This simplifies to:
-7/1 = b
So the value of b is -7
It is worth noting that the solution for b is a negative number, it is possible that the original problem is not well defined and it might not have a solution.