[tex]\frac{x}{3} -2[/tex]
Rest:
[tex]x-\frac{x}{3} +2=\frac{2x}{3} +2[/tex]
[tex]\frac{2}{7} \times [x-(\frac{x}{3} -2)]+10=\frac{2}{7} \times(\frac{2x}{3}+2)+10=\frac{4x}{21}+\frac{4}{7}+10[/tex]
Rest:
[tex]\frac{2x}{3}+2-\frac{4x}{21}-\frac{4}{7} -10=\frac{10x}{21}-\frac{74}{7}+2 = \frac{10x}{21}-\frac{60}{7}[/tex]
[tex]\frac{1}{2}\times ( \frac{10x}{21} -\frac{60}{7} )+5=\frac{10x}{42} -\frac{60}{14} +5[/tex]
45km
[tex]\frac{x}{3} -2+\frac{4x}{21}+\frac{4}{7} +10+\frac{10x}{42} -\frac{60}{14} +5+45=x[/tex]
Numitorul comun este 42
Amplificam fractiile corespunzator si eliminam numitorul, vom obtine:
14x-84+8x+24+420+10x-180+210+1890=42x
42x-32x=2280
10x=2280
x=228 km