8y-9y²=-40+6²-(3y)²
8y-9y²+9y²=-40+36
8y=-4|:8
y=(-4)/8
y=(-½)
y=-0,5
15,25+27/127=15 1/4+27/127=
15+(1/4+27/127)=15+(127+98)/(4*127)=
15+225/508=15 225/508
1) <span>5x^2+2x-3
D=4+60=64
x=(-2+8)/10=6/10=3/5
x=(-2-8)/10=-1
5*(x-3/5)(x+1)=(5x-3)(x+1)
2) </span><span>3x^2+4x-7
</span> D=16+ 84=100
х=(-4+10)/6=1
х=(-4-10)/6=-14/6=-7/3
<span>3*(х+ 7/3)(х-1)=(3х+7)(х-1)
</span>
3) <span>-3x^2+5x-8
</span> D=25+96=121
x=(-5+11)/(-6)= -1
x=(-5-11)/(-6)= -16/(-6) =8/3
-3*(x- 8/3)(x+1)=(-3x+8)(x+1)
h² = (5x)²-11²
h² = (2x)²-4²
25x²-121 = 4x²-16
21x² = 105
x² = 5
х = +- корень из 5
h² = (2x)²-4² = 4*5 - 16 = 4
h = 2