Question 717873
add the 'like terms'
start with the {{{x^2}}} terms
i.e.
-3+8 = +5. so we have {{{5x^2}}}
now do the x terms
i.e.
-8+-2 = -10, so we have -10x
and finally the constants
+1+-9 = -8
putting them all back together gives
{{{5x^2-10x-8}}}