if a car had traveled 30 kmh faster than it actually did , the trip would have lasted 30 minutes less . if the car went exactly 90 km , at what speed did it travel ?
"time = distance / speed difference in time = 1 / 2 hrs 90 / x - 90 / ( x + 30 ) = 1 / 2 substitute the value of x from the options . - - > x = 60 - - > 90 / 60 - 90 / 90 = 3 / 2 - 1 = 1 / 2 answer : c"
divide(subtract(sqrt(add(multiply(multiply(const_2, multiply(90, 30)), const_4), power(30, const_2))), 30), const_2)