good morning Kingsley: The question is asking you to find the value of x that makes the equation equal to zero. This is the same thing as asking where does the graph cross the x-axis.
Since you have to parts (two things in parenthesis) set each equal to zero:
x^2 -3 = 0 and solve for x. Remember when you take the square root of 3 you will have a positive and a negative answer!
x^2 +3 -4 = 0 and solve for x by factoring into two parts (x+4)(x-3) and set each of these equal to zero.
Does that make sense?
You will have four answers or four places the graph crosses the x-axis.