Question

x2-10x+18 find d zeros of polynomial

Answer 1

by comparing with equation
$a x^{2} +bx+c=0$
for equation
$x^{2} -10x+18=0,a=1,b=-10,c=18$
sub. a,b and c in the formula 
$x= \frac{-b+ \sqrt{ b^{2}-4ac } }{2a}, \frac{-b- \sqrt{ b^{2}-4ac } }{2a}$
u can find that roots are $5- \sqrt{7},5+ \sqrt{7}$

Answer 2

split the middle term
x2-4x-6x+18
x(x-4)-3(2x+6)
(x-3)(2x+6)