Answer:
x - intercepts: (4,0) and (-2,0)
vertex: (1/2 , - 17/2)
Step-by-step explanation:
Part A
To find the x-intercepts you have to set y=0
(x-4) (x+2) = 0
Separate the parenthesis. Solve for x
x-4 = 0
x= 4
x+2 = 0
x= -2
x - intercepts: (4,0) and (-2,0)
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Part B
vertex formula for the x: coordinate : -b/2a
Expand the function.
y = 2x^2-2x-8
a = 2
b = -2
c= -8
-b/2a = -(-2)/2(2) = 1/2
vertex x- coordinate: 1/2
Substitute 1/2 back into every "x" in the function to find the "Y" for the vertex.
y = 2(1/2)^2 -2(1/2) -8
y = -17/2
vertex: (1/2 , - 17/2)
