Question 1044982


{{{s(x)=x-1}}}
{{{t(x)=3x+4}}}



{{{(s-t)(x)=s(x)-t(x)=x-1-(3x+4)=x-1-3x-4=-2x-5}}}

{{{(s*t)(x)=(x-1)(3x+4)=x*3x+x*4-1*3x-1*4=3x^2+4x-3x-4=3x^2+x-4}}}

{{{(s+t)(x)=x-1+3x+4=4x+3}}}, than 
{{{(s+t)(-2)=4(-2)+3=-8+3=-5}}}