x=viteza automobil 1
x-10 =viteza automobil 2
45 min= 0,75 ore
540/x+0,75 = 540/(x-10)
(540+0,75x)/x =540/(x-10)
540x+0,75x²-5400-7,5x=540x
0,75x²-7,5x-5400=0
x²-10x-7200=0
x²-90x+80x-7200=0
x(x-90)+80(x-90)=0
(x-90)(x+80)=0
x-90=0
x=90 km/h viteza automobil 1
90-10=80 km/ora viteza automobil 2