If using the method of completing the square to solve the quadratic equation x^2-11x-38=0, which number would have to be added to "complete the square"?

The function ƒ is defined by ƒ(x) = (x + 3)(x + 1). the graph of ƒ in the xy-plane is a parabola. which interval contains the x-coordinate of the vertex of the graph of ƒ?

The table shows the results of three plays in a football game. what is the net result of the three plays? football game 1st play 5 yards 2nd play -9 yards 3rd play 12 yards

Can some one explain this i got sent this. is this a threat i’m scared