Тест 7
1. 12x²+4x-1=0
D=16+48=64=8²
x1=(-4-8)/24= -0.5= -1/2
x2=(-4+8)/24=4/24=1/6
2. 2x²-5x=6-4x
2x²-5x-6+4x=0
2x²-x-6=0
D=1+48=49=7²
x1=(1-7)/4=-6/4= -3/2
x2=(1+7)/4=2
3. 0.5x²+3x+4=0
D=9-8=1
x1=(-3-1)/1= -4
x2=(-3+1)/1= -2
6. 10x²-7x=0
x(10x-7)=0, x1=0
10x-7=0, 10x=7, x2=0.7
7. 25x²=9
x²=9/25, x1=3/5, x2= -3/5