Consider the Quadratic function fx x2 3x 40 Its vertex is

Consider the Quadratic function f(x) = x^2 - 3x - 40. Its vertex is (,) Its largest x-intercept is x =. Its y-intercept is y =.

f(x) = x^2 - 3x -40

for a quadratice function : f(x) = ax^2 +bx +c

Vertex : h = -b/2a k = f(h)

h = -(-3)/(2*1) = 3/2

k = f(3/2) = 9/4 - 9/2 -40 = (9 -18 - 160)/4 = -169/4

Vertex ( 3/2 , -169/4)

X intercept: x^2 -3x -40 =0

x^2 -8x +5x -40 =0

x( x-8) +5( x- 8) =0 -----> x = -5 ; x= 8

Y intercept : f(0) = -40