$a, -x+8=-7$
$⇔-x=-7-8$
$⇔-x=-15$
$⇔x=15$
$b, -148-2x=-260$
$⇔-2x=-260+148$
$⇔-2x=-112$
$⇔x=56$
$c, 12x+450=15x-162$
$⇔12x-15x=-162-450$
$⇔-3x=-612$
$⇔x=204$
$d, \left \{ {{-(x-5)=-7} \atop {-(5-x)=-7}} \right.$
$⇔\left \{ {{-x+5=-7} \atop {-5+x=-7}} \right.$
$⇔\left \{ {{-x=-12} \atop {x=-7+5}} \right.$
$⇔\left \{ {{x=12} \atop {x=-2}} \right.$
$e, (x-2)(5-x)=0$
$⇔\left \{ {{x-2=0} \atop {5-x=0}} \right.$
$⇔\left \{ {{x=2} \atop {x=5}} \right.$
$g, x³=-64$
$⇔x³=-4³$
$⇔x=-4$
$h, (x-1)^5=-32$
$⇔(x-1)^5=-2^5$
$⇔x-1=-2$
$⇔x=-2+1$
$⇔x=-1$
$i, -(x+1)²+81=0$
$⇔-(x+1)²=-81$
$⇔\left \{ {{x+1=9} \atop {x+1=-9}} \right.$
$⇔\left \{ {{x=8} \atop {x=-10}} \right.$
