2) The expression x + 6x² + 36x + 216 is equivalent to (x + 6)(x2 + 36). At what point(s) does the graph of the function f(x) = x+ 6x2 + 36x + 216 intersect the x-axis?
A) (6.0)
B) (-6,0)
C) (-36,0)
D) (-6,0) and (6.0)

a is the right answer

answer: ♡♡♡♡♡♡♡♡♡♡

step-by-step explanation:

let's call the solutions x₁ = (5 - 2√7)/3 and x₂ = (5 + 2√7)/3

then the equation is (x-x₁)(x-x₂) = 0

if you fill that in you get a lot of numbers which you can recognize as ax²+bx+c=0.

step-by-step explanation:

you can see that a=1 (there is just an x²)

b = (-5 -2√7 + 2√7 - 5)/3 = -10/3

c = -2√7)/3 ) * (-5+2√7)/3) = -1/3

so your answer is 3x^2 – 10x – 1 = 0