Answer:
(3,2)
Step-by-step explanation:
Since both equations are equal to each others.
2x-4=-2x+8
2x+2x=8+4
4x=12
x=3
Substitute x = 3 in any given equations but I will substitute in the first equation.
y = 2(3)-4
y = 6-4
y = 2
The average speed of the whole journey of car based mentioned speeds is 48 km/hr.
The average speed is calculated by the formula -
average speed = total distance covered ÷ total time taken. The total distance covered is sum of distance of first and return journey. Total distance covered = 100 + 100
Performing addition
Total distance covered = 200 kilometres
Now total time taken = time taken on first journey + time taken for return journey
Total time taken = distance/speed + distance/return speed
Total time taken = 100/60 + 100/40
Performing division
Total time taken = 5/3 + 5/2
Total time taken = 10 + 15/6
Total time taken = 25/6 hour
Average speed = 200/(25/6)
Average speed = (200×6)/25
Performing division and multiplication
Average speed = 48 km/hr
Learn more about speed -
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