the vertex of this parabola is at 4,-3 when the x value is 5 the y value is -6 what's the coefficient of the squared expression in the parabolas equation A-2 b2 c3 d-3

d) -3

Step-by-step explanation:

The equation of a parabola in vertex form is given as:

y = a(x - h)² + k. Where (h, k) is the vertex of the parabola.

Given that the vertex of the parabola is at (4,-3) i.e h = 4 and k = -3.

The equation of the parabola is given as:

y = a(x - 4)² + (-3)

y = a(x² - 8x + 16) - 3

y = ax² - 8ax + 16a - 3

Given that when x = 5, y = -6. i.e:

-6 = a(5)² - 8a(5) + 16a - 3

- 6 = 25a - 40a + 16a - 3

-6 + 3 = a

a = -3