х2-110х+216=0
<var>х1,х2=-b+- корень из D /2a</var>
<var> х1=110+ корень 12100-864/2</var>
<var> х1=110-106/2</var>
<var> х1=2</var>
<var> х2=110+106/2</var>
<var> х2=108 </var>
√х+3+√х-4=√30
(√х+3+√х-4)^2=(√30)^2
х+3+2√(х+3)(х-4)+х-4=30
2х-1+2√(х+3)(х-4)=30
2√(х+3)(х-4)=31-2х
(2√(х+3)(х-4))^2=(31-2х)^2
4(х+3)(х-4)=961-124х+4х^2
4х^2-16х+12х-48=961-124х+4х^2
-4х-48=961-124х
120х=961+48
120х=1009
х=1009/120
<span>1) 2х^2-5х-3=0
Д=(-5)^2-4*2*(-3)=25+24=49
x1=5+7/4=3 x2=5-7/4=-2/4=-1/2
2)</span><span>3х^2-3х+1=0
Д=(-3)^2-4*3*1=9-12=-3 нет решения
3)</span><span>3х^2-8х+5=0
Д=(-8)^2-4*3*5=64-60=4
x1=8+2/9=10/6=5/3 x2=8-2/6=1
4)</span><span>х^2+9х-22=0
Д=9^2-4*1*(-22)=81+88=169
x1=-9+13/2=4/2=2 x2=-9-13/2=-22/2=-11
5)</span><span>5х^2+9х+4=0
Д=9^2-4*5*4=81-80=1
x1=-9-1/10=-10/10=-1 x2=-9+1/10=-8/10=-4/5
6)</span><span>7х^2-11х-6=0
Д=(-11)^2-4*7*(-6)= 121+168=289
x1=11-17/14=6/14=3/7 x2=11+17/14=28/14=7</span>