Question

A train travels at a certain average speed for a distance of 54 km and then travels a distance of 63 km at an average speed of 6 km/h more than the first speed. Its takes 3 hours to complete the total journey. what is its First speed?
i need this question urgent please ​

Answer 1

let speed for 54 km is x km /hr
for next 63 km, (x + 6)km/hr
total distance = 117 km
time = 3hrs
54 over straight x plus fraction numerator 63 over denominator straight x plus 6 end fraction equals 3
54 open parentheses straight x plus 6 close parentheses plus 63 straight x equals 3 open parentheses straight x close parentheses open parentheses straight x plus 6 close parentheses
54 straight x plus 324 space plus space 63 straight x equals 3 straight x squared plus 18 straight x
3 straight x squared minus 99 straight x minus 324 equals 0
straight x squared minus 33 straight x minus 108 equals 0
using space fromula
straight x equals 36