0,2x2+0,6x=2,5x-0,5x3
0,5x3+0,2x2-1,9x=0
x(0,5x2+0,2x-1,9)=0
x(5x2+2x-19)=0
D=4+380=384
x=0; (-1+√96)/5; (-1-√96)/5
(x²-2y²)²=x⁴-4x²y²+4y⁴
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(a-4)(a+3)=a^2-4a+3a-12=a^2-a-12
(m-11)(m-2)=m^2-11m-2m+22=m^2-13m+22
(y-4)(3y-4)=3y^2-12y-4y+16=3y^2-16y+16
(6a-5)(6a-1)=36a^2-30a-6a+5=36a^2-36a+5
(2b+3)(3b-2)=6b^2+9b-4b-6=6b^2+5b-6
(7z-2)(z-3)=7z^2-2z-21z+6=7z^2-23z+6