if a car had traveled 10 kmh faster than it actually did , the trip would have lasted 30 minutes less . if the car went exactly 30 km , at what speed did it travel ?
"time = distance / speed difference in time = 1 / 2 hrs 30 / x - 30 / ( x + 10 ) = 1 / 2 substitute the value of x from the options . - - > x = 20 - - > 30 / 20 - 30 / 30 = 3 / 2 - 1 = 1 / 2 answer : a"
divide(subtract(sqrt(add(multiply(multiply(const_2, multiply(30, 10)), const_4), power(10, const_2))), 10), const_2)