Răspuns :
Răspuns:
a) x1=12 , x2=-12
b) x1=0 , x2=-7/5
c)x1=-2/3 , x2=-1
d) x1=-1 , x2=-9
Explicație pas cu pas:
a)
x²-144=0
x²=144
x²=144
x=±12
x=±12
x=-12
x=12
x1=-12 , x2=12
b)
5x²+7x=0
x×(5x+7)=0
x=0
x= - 7 supra 5
x1= - 7 supra 5 , x2=0
forma alternativa:
x1= - - 1,4 , x2=0
c)
3x²+5x+2
3x²+3x+2x+2
3x²+3x+2x+2
3x×(x+1)+2x+2
3x×(x+1)+2x+2
3x×(x+1)+2(x+1)
3x×(x+1)+2(x+1)
(x+1)×(3x+2)
d)
x²+10x+9=0
x²+9x+x+0=0
x²+9x+x+0=0
x×(x+9)+x+9=0
x×(x+9)+x+9=0
(x+9)×(x+1)=0
(x+9)×(x+1)=0
x+9=0
x+1+0
x+9=0
x+1=0
x=-9
x=-1
x=-9
x=-1
x1=-9 , x2=-1