Part A
The given equation is
as there is only one variable, the equation either has 1 solution or no solution. However, note that on the left we have a polynomial of degree 1 (a line), whenever we make it equal to a constant, we always have a solution. So in this case the solution is 1.
Part B
Now, to solve this equation first we divide both sides by 5. So we get
Then, we add 3 on both sides to get
Finally we divide both sides by 2 to get
so the unique solution of the equation is x=2