Driving towards a deer; Constant

[burton95]

Homework Statement

driving down K10 highway (70 mph speed limit, this info is not given) one night a deer jumps out in front of you at a distance of 100 m. You don't notice for 1.5 s. As you are skidding towards the deer your acceleration is -5 m/s. What is the max initial speed you could have had to avoid hitting the deer?

Homework Equations

Constant motion equations

The Attempt at a Solution

70 mph = 31.2861 m/s

1.5 * 31.2861 = 46.9292 meters traveled b/w deer jumping in front of car and when I hit the brakes.

100-46.9292 = 53.0708 Meters to slow to a velocity of 0

a= -5 m/s².

V₀ = 31.2861 m/s

Δx = 0 - 53.0708 = -53.0708 m

v_f= 0

So what max speed will allow my v_f→0 over -53.0708 meters at an acceleration of -5 m/s. I have only calculated numbers greater than my v₀

 

[burton95]

never mind I got it. Thanks anyway