Question

If x-5 is a factor of p(x) = x^3 + ax^2 +bc - 20

Answer 1

$\huge\bold{Solution}$


Let ( x - 5 ) = 0

=> x = 5 is a factor of p ( x )

Then,

$p(5) = 5 {}^{3} + a(5 {}^{2} ) + bc - 20 \\ \\ = > 125 + 25a + bc - 20 \\ \\ = > 25a + bc + 105 \\ \\ = > 5(5a + bc + 21) = 0 \\ \\ = > 5a + bc + 21$


$\textbf{Hope it helps!!!}$