Ответы
3x^2-12=0
3x^2=12
x^2=12/3
x^2=4
x=2
2x^2+6x=0
2x(x+3)=0
2x=0 x+3=0
x=0 x=-3
1.8x^2=0
x^2=0
x=0
x^2+9=0
(x+3)(x-3)=0
x=+-3
7x^2-14=0
7x^2=14
x^2=14/7
x^2=2
x=+-корень из 2
x^2-3x=0
x(x-3)=0
x=0 x-3=0
x=3
-2/3 x^2=0
x^2=0
x=0
6x^2+24=0
6x^2=-24
x^2=-24/6
x^2=-4
10x+2x^2=0
2x(5+x)=0
2x=0 5+x=0
x=0 x=-5
15-5x^2=0
-5x^2=-15
5x^2=15
x^2=15/5
x^2=3
x=+- корень из 3
4.9x^2=0
x^2=0
x=0
6.3x-0.7x^2=0
63x-7x^2=0
7x(9-x)=0
7x=0 9-x=0
x=0 x=9
2x^2-18=0
2x^2=18
x^2=18/2
x^2=9
x=+-3
3x^2-12x=0
3x(x-4)=0
3x=0 x-4=0
x=0 x=4
2.7x^2=0
x^2=0
x=0
x^2+16=0
x=+-4
6x^2-18=0
6x^2=18
x^2=18/6
x^2=3
x=+-корень из 3
x^2-5x=0
x(x-5)=0
x=0 x-5=0
x=5
-3/7 x^2=0
x^2=0
x=0
4x^2+36=0
4x^2=-36
x^2=-9
6x-3x^2=0
3x(2-x)=0
3x=0 2-x=0
x=0 x=2
12+4x^2=0
4x^2=-12
x^2=-3
0.2x-1.8x^2=0
2x-18x^2=0
2x(1-9x)=0
2x=0 1-9x=0
x=0 x=1/9
вот некоторые: остальные не смогла решить