What are the solutions to the inequality (x-3)(x+5) so?

Given the following statements, which is the best

Find the gradient of f(x,y,z)equals=left parenthesis x squared plus y squared plus z squared right parenthesis superscript negative 1 divided by 2 baseline plus ln left parenthesis x right parenthesis x2+y2+z2−1/2+ln(xyz) at the point left parenthesis negative 2 comma 1 comma negative 2 right parenthesis(−2,1,−2).

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?