Richard asks…Math Question!!! best answer gets 10 points!?A man with a reaction time of 0.6 seconds is driving through a school zone. His total stopping distance is 6 metres. If he is driving at x metres per second, explain why x^2 + 9x - 90 = 0.
Also, find the speed of the car in Kilometers per hour.Nancy answers:X² + 9x - 90 = 0.
This factors to (x + 15)(x - 6) = 0, so
x = -15 or x = 6.
Discard the negative possibility, since he's not driving backward; therefore x = 6.
Check: 6² + 9(6)
