(k-m)(k+m) = k² - m²
(2x+1)(2x-1) = 4x² - 1
(3a-5b)(3a+5b) = 9a² - 25b²
(m+n³)(m-n³) = m² - n⁶
x²-y² = (x+y)(x-y)
m²-9 = (m-3)(m+3)
1) 3,5-2,3=х+3х
1,2=4х
х=1,2:4
х=0,3
2) -4х+4,5х=-1-0,1
0,5х=-1,1
х=-1,1:0,5
х=-2,2
3y^2-5y+2y^3=3y^2-3y-2y+2y^3=3y(y-1)+2y(y^2-1)=3y(y-1)+2y(y-1)(y+1)=y(y-1)(3+2(y+1))=(y-1)(3+2y+2)=y(y-1)(5+2y)