According to the rational root theorem, -2/5 is a potential rational root of which function? f(x) = 4x4 – 7x2 + x + 25 f(x) = 9x4 – 7x2 + x + 10 f(x) = 10x4 – 7x2 + x + 9 f(x) = 25x4 – 7x2 + x + 4

By the rational root theorem, the numerator of any possible rational root must be a factor of the constant term and the numerator must be a factor of the coefficient of the largest exponent term. the denominator of 5 means the leading coefficient must be a multiple of 5, which rules out the first two answers. the numerator of-2 required the constant to be even, so only the last answer is possible.
f(x)=25x⁴ - 7x² +x +4

In this problem it decreased 20%