Flying

The airplane from Prague to Bratislava was flying at a speed of 60 km/h less and back by 70 km/h greater than the original speed. What was the original speed if the plane returned to Prague according to the timetable?

Correct answer:

v =  840 km/h

Step-by-step explanation:

s/(v60) + s/(v+70) = 2s/v 1/(v60) + 1/(v+70) = 2/v v(v+70)+v(v60)=2 (v+70)(v60) 10v=8400 v=8400/10=840=840 km/h

Equation is non-linear.

Calculation:

Equation is linear and have one solution:

-10v+8400=0

x=840

Our simple equation calculator calculates it.