Odpowiedź:
3. a) [tex] {x}^{2} + x - 1 = ( - 1)^{2} + ( - 1) - 1 = 1 - 1 - 1 = - 2[/tex]
b) [tex]2( - x + 4) = - 2x + 8 = ( - 2) \times ( - 10) + 8 = 20 + 8 = 28[/tex]
c) [tex]1 - y + x = 1 - ( - 1) + ( - 2) = 1 + 1 - 2 = 0[/tex]
4. a) 5x+15y=5(x+3y)
b) 5m+5=5(m+1)
c) 6b-12=6(b-2)
d) [tex] \frac{1}{3} xy - \frac{2}{6} x = \frac{1}{3} x(y - 1)[/tex]
e) [tex]12 {a}^{2} - 18ab = 6a(2a - 3b)[/tex]
f) [tex] - 6 {a}^{2} - 2a = - 2a(3a + 1)[/tex]
