(x+3 + 18/(x-3))*(2x² -12x +18)/(x²+9) =
<span>( ( (x+3)(x-3) + 18 ) /(x-3) )*2(x² -6x +9)/(x²+9) =
</span>( (x²-9 + 18) /(x-3))*2(x-3)²/(x²+9) =((x²+9) /(x-3))*2(x-3)<span>²/(x²+9) =
</span><span>2(x-3).</span>
9x/9+x/9=-30/9
9x+x=-30
10x=-30
x=-3
А)=4(8х²-9у²)=32х²-36у²
б)=а²-8а+16-(а²+8а+16)=-16а
в)=16а²+40ab+25b²
= X * ( Y + Z) + 6 * ( Y + Z) = ( Y + Z) * ( X + 6 )