Odpowiedź:
[tex](2x - 5)(4x + 2) = 8 {x}^{2} + 4x - 20x - 10 = 8 {x}^{2} - 16x - 10[/tex]
[tex](x + 2y)(x - 3y) = {x}^{2} - 3xy + 2xy - 6 {y}^{2} = {x}^{2} - xy - 6 {y}^{2} [/tex]
[tex](3 + a)(a + 3) = 3a + 9 + {a}^{2} + 3a = {a}^{2} + 6a + 9[/tex]
[tex](4x - 5)(2x - 2) = 8 {x}^{2} - 8x - 10x + 10 = 8 {x}^{2} - 18x + 10[/tex]
