[tex]1)\\\\x=-5\\\\x^2+ x =(-5)^2+(-5)=25-5=20\\\\2)\\\\x=-2\ \ i\ \ z=7\\\\x^2- z (x+1)=(-2)^2-7(-2+1)=4-7*1=4-7=-3[/tex]
[tex]3)\\\\x=-7\\\\ 5x^3 + 4-7x=5*(-7)^3+4-7*(-7)=5*(-343)+4+49=-1715+53= 1662\\\\4)\\\\x= 3\ \ i \ \ y= -1 \\\\3x-y (2x- y) =3 *3- (-1) (2*3- (-1)) =9+(6+1) =9+7=16[/tex]
[tex]5)\\\\a=-7\\\\ \frac{\not{a}^1 (a-2) (a+2)^2}{\not{a}^1}= (-7-2) (-7+2)^2=(-9)*(-5)^2=(-9)*25=-225[/tex]
