1) у²=0,09⇒y=±0.3
2) х²=3⇒x=±√3
3) х²+5=30⇒x²=25⇒x=±5
4) 5х²+7х=0⇒x(5x+7)=0⇒x=0 и x=-7/5
5) 4m²-3m=0⇒m(4m-3)=0⇒x=0 и x=3/4
6) 3u²+7=6u+7⇒3u²-6u=0⇒3u(u-2)=0⇒u=0 и u=2
7) 2m²-3m=8-3m⇒2m²=8⇒m²=4⇒m=±2
8) 10-2х²=х²-х+10⇒x-3x²=0⇒x=0 и x=1/3
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