How do you use the rational root theorem to find the roots of #P(x) = 0.25x^2 - 12x + 23#?
1 Answer
Jan 8, 2017
Explanation:
First multiply by
#4P(x) = 4(0.25x^2-12x+23) = x^2-48x+92#
By the rational root theorem, any rational zeros of
That means that the only possible rational zeros are:
#+-1, +-2, +-4, +-23, +-46, +-92#
Trying each in turn we soon find:
#P(color(blue)(2)) = 0.25(color(blue)(2))^2-12(color(blue)(2))+23 = 1-24+23 = 0#
So
#x^2-48x+92 = (x-2)(x-46)#
So the other zero of