Bonjour,
a)
[tex]\frac{x}{7}=\frac{4}{7}\\\\\frac{x}{7}*7=\frac{4}{7}*7\\\\x = \frac{28}{7}\\\\x = 4[/tex]
b)
[tex]\frac{5}{4}x=\frac{2}{3}\\\\\frac{5}{4}* \frac{4}{5}x=\frac{2}{3}*\frac{4}{5}\\\\\frac{1}{5}*5x=\frac{8}{15}\\\\ x=\frac{8}{15}\\[/tex]
2)
[tex]\frac{x}{7}=\frac{6}{5}\\\\ \frac{x}{7} *7=\frac{6}{5}*7\\\\x=\frac{42}{5}[/tex]
2)
[tex]\frac{5}{4}x=-3\\\\\frac{5}{4}x*\frac{4}{5} =-3*\frac{4}{5} \\\\\frac{1}{5}*5x=-\frac{12}{5}\\\\x = -\frac{12}{5}[/tex]
3)
[tex]\frac{-2x}{5}=\frac{3}{2}\\\\\frac{-2x}{5}*5=\frac{3}{2}*5\\\\-2x=\frac{15}{2}\\\\\frac{-2x}{-2} = \frac{\frac{15}{2}}{-2}\\\\x = \frac{15}{2}*\frac{1}{-2}\\\\x = \frac{15}{-4}[/tex]
3)
[tex]-\frac{4}{7}x=-\frac{2}{3}\\\\-\frac{7}{4}* -\frac{4}{7}x=-\frac{2}{3}*-\frac{7}{4} \\\\\frac{1}{4}*4x=\frac{14}{12}\\\\x = \frac{7}{6}[/tex]
4)
[tex]\frac{5x}{2} =3\\\\\frac{2}{5} *\frac{5x}{2} =3*\frac{2}{5} \\\\\frac{1}{5}*5x=\frac{6}{5}\\\\x = \frac{6}{5}[/tex]
4)
[tex]3x = \frac{3}{2}\\\\\frac{3x}{3} = \frac{\frac{3}{2}}{3} \\\\x = \frac{3}{2}*\frac{1}{3}\\\\x = \frac{3}{6}\\\\x = \frac{1}{2}[/tex]
J’espère t’avoir aidé.
Si tu as des questions n’hésites pas à me les demander.
Bonne journée et bonne continuation.
