Вроде бы так
По моим подсчетам
6а
7в
8г
9г
Y=x²-10x+9
y=(x-5)²-25+9
y=(x-5)²-16
V(5,-16)
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c x: y=0, (x-5)²-16=0,(x-5)²-4²=0,(x-5+4)(x-5-4)=0,(x-1)(x-9)=0
a)x-1=0,x=1, X1(1,0)
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b)x-9=0, x=9, X2(9,0)
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c y: x=0, y=(0-5)²-16=(-5)²-16=25-16=9
Y(0,9)
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<span>2d-4y</span> - <span>7d+3y </span> = <span>(2d-4y)*( 2d-3y)</span><span>-( 7d+3y )*( 2d-3y )</span> =