Bonjour !
Ex 27 :
a)
[tex]9 - 2a = -3 \\ - 2a = - 12 \\ a = \frac{ - 12}{ - 2} = 6[/tex]
b)
[tex]4t + 3 = -2t \\ 6t = - 3 \\ t = \frac{ - 3}{6} = - \frac{1}{2} [/tex]
Ex 28 :
a)
[tex]5x + 3 = 0 \\5x = -3 \\ x = -\frac{3}{5} [/tex]
b)
[tex]0= - 7y + 5 \\ - 7y = - 5 \\ y = \frac{5}{7} [/tex]
Ex 29 :
a)
[tex]1 + 2x = 3x - 7 \\ 2x = 3x - 8 \\ - x = - 8 \\ x = 8[/tex]
b)
[tex]7t + 22 = 14 - 4t \\ 7t + 8 = - 4t \\ 11t = - 8 \\ t = - \frac{8}{11} [/tex]
Bonne journée
