Acar completes a journey at an average speed of 40km/h. at what speed must it travel on the return journey if the average speed for the complete journey is 60km/h?

The distance, s = 40t₁ where t₁ is the time to complete the outward journey.
The same distance = vt₂ where t₂ is the time to complete the return journey at speed v.
For the whole journey, 2s=60(t₁+t₂). Therefore s=30(t₁+t₂)=40t₁=vt₂.
30t₁+30t₂=40t₁, 10t₁=30t₂, t₁=3t₂, so s=120t₂=vt₂ and v=120kph.

Iwould like to think so. what’s the question you need with?

Y= -2x-1 the negative in front of the 2 is because the slope is negative and the -1 is because it’s down 1 on the y axis.