[tex] \frac{3}{5} e-6=- \frac{2}{5}(e-10)-7 [/tex]
[tex] \frac{3}{5} e-6=- \frac{2}{5} e- \frac{2}{5}*(-10) -7 \\ \frac{3}{5} e-6=- \frac{2}{5} e+ \frac{20}{5} -7= \frac{3}{5} e-6=- \frac{2}{5} e+4 -7= \\ [/tex]
[tex] \frac{3}{5}e-6=- \frac{2}{5} e-3[/tex] /*5
3e-18=-2e-15 /+15
3e-3=-2e /+2e
5e-3=0 /+3
5e=3
e=[tex] \frac{3}{5} [/tex]