Odpowiedź:
a)
[tex](x - 7)(4x + 6) = 4 {x}^{2} - 22x - 42[/tex]
b)
[tex]( {x}^{2} - 3x + 2) \times 5x = 5 {x}^{3} - 15 {x}^{2} + 10x[/tex]
c)
[tex](8 {x}^{2} + 28x - 4) \div 2 - (x + 1) \times 3 = 4 {x}^{2} + 11x - 5[/tex]
d)
[tex](a - 2b)( - 3b - a) = - ab - {a}^{2} + 6 {b}^{2} [/tex]
