[tex]bonjour, \\\\\\4 x - 5 = 7 \\4 x = 7 + 5 = 12\\x = 3 \\\\13.8 = 5 + 1.1 x \\- 1.1 x = 5 - 13.8 = - 8.8\\x = 8 \\\\5 x /2 - 3 = 2 \\5 x /2 - 6 /2 = 4 /2 \\5 x = 4 + 6 = 10 \\x = 2 \\\\x /4 + 5 = 7 \\x /4 + 20/4 = 28/4\\x = 28 - 20 = 8\\x = 8 \\\\- 4 x = 6 /10 \\- 40 x = 6 \\x = - 6/40 = - 3/20 \\\\x /9 = 4 /3 \\3 x = 36\\x = 12 \\\\[/tex]
