Amira's average speed in km/h for the final 10 km of the journey is
[tex] \frac{600}{x - 25.} [/tex]
Her average speed for the first 30 km of the journey is 8km/h slower than her average speed for the final 10km.

form an equation in x and show that it simplifies to
[tex] {x }^{2} + 125x - 5625 = 0[/tex]