<span>1)</span>3х²-27=0 3) 4х²+20х=0 4)<span> 3х²-12х=0</span>
3х²=27 4x(x+5)=0 3x(x-4)=0
х²=9 4x=0 3x=0
<span><span> x=3 x=0 x=0</span></span>
<span><span> ответ:3 x+5=0 x-4=0</span></span>
<span><span>2)<span>2х²-32=0 x=-5 x=4</span></span></span>
<span><span><span>2х²=32 ответ:-5;0 ответ:4;0</span></span></span>
<span><span><span>х²=16 </span></span></span>
<span><span><span>x=4</span></span></span>
ответ:4