Answer:
Step-by-step explanation:
Let the number of miles is x.
Then for each company we have total charge of:
Since A = B, solve for x:
Let no of miles be y
[tex]\\ \sf\longmapsto A=B[/tex]
[tex]\\ \sf\longmapsto 0.7y+70=0.8y+20[/tex]
[tex]\\ \sf\longmapsto 0.8y-0.7y=70-20[/tex]
[tex]\\ \sf\longmapsto 0.1y=50[/tex]
[tex]\\ \sf\longmapsto y=\dfrac{50}{0.1}[/tex]
[tex]\\ \sf\longmapsto y=500miles[/tex]