Respuesta :

Answer:

the vertex of this parabola is at (5/2, 47/4)

Step-by-step explanation:

Y=x^2+5x-7 is written in 'standard form' for a quadratic.  Comparing this to

y = ax^2 + 5x - 7, we see that a = 1 and b = 5.  

                                                                                          -b

The formula for the x-coordinate of the vertex is x = --------

                                                               5                         2a

which in this case has the value x = ------- = 5/2

                                                             2(1)

Now use the quadratic formula to find the y-value of the vertex:

y = (5/2)^2 + 5(5/2) - 7, or

y  =  25/4 + 25/2 - 7, or

y  = 11.75 or 11 3/4

Thus the vertex of this parabola is at (5/2, 47/4)