Решите полностью если можно 1) x²-4x+3=0 2) x²+9x=0 3) 7x²-x-8=0 4) 2x²-50=0 5) x²+27-63=0 6) 0.9x-3x²=0 7) 2x²-57+2=0 8) x²-2x-6=0

1) Д = -4^2 -4*1*3 = 4
x1 = 1
x2 = 3
2) x(x+9) = 0
x= 0  x+9 = 0
        x = -9
3) D = -1^2 -(-4)*7*8 = 225
x1 = -1
x2 = 8/7
4) 2x^2 = 50
x^2 = 50/2
x^2 = 25 
x1 = 5      x2 = -5
5) x^2 =36
x1 = 6    x2 = -6
6) 0.3x(3 - 10x) = 0
0.3 x =0      3-10x =0
x = 0             10x = 3
                      x =  3/10 = 0.3
6)  2x²-57+2=0
2x^2 -55 = 0
2x^2 = 55
x^2 = 55/2
x^2 = 27.5
x = корень 27,5
7)  x²-2x-6=0
D = -2^2 -4*(-4)*1*6 =28
x1 = (2 + кореннь28) /2
х2 = (2-корень28)/2