# math

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Solve this :
(8x^3 ) - (168x^2) + ( 864x) = 1120

• math -

(8x^3 ) - (168x^2) + ( 864x) = 1120 divide by 8
(x^3 ) - (21x^2) + ( 108x) - 140 = 0

I tried x = 2 and it worked, so x-2 is a factor
using synthetic division I founs
(x-2)(x^2- 19x + 70) = 0

(x-2)(x-14)(x-5)=0

so x 2, x = 14, or x = 5

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