Question

What is the vertex of the graph of y = 5(x + 4)2 + 3?

A: -4,3
B: 4,3
C: 3,4
D: 3,-4

Answer 1

The vertex form: y = a(x - h)² + k

(h; k) - coordinates of the vertex

Therefore:

y = 5(x + 4)² + 3
vertex: (-4; 3)

Answer: A: -4, 3

Answer 2

A: -4,3 The x coordinate of the vertex is given by x = -b/2a and the y coordinate of the vertex is given by y= f( -b/2a), we need to transform the equation to the form ax^2 + bx + c We have: 5(x+4)^2+3 = 5x^2+ 20x + 23 Then we substitute x= -20/2*5 y= f(-20/2*5) = -4 = f(-4) =3 So V(-4,3)