Highway engineers often use quadratic functions to model safe stopping distances for cars like 1/2x quantity squared + 11/5x is used to model the safe stopping distance for car traveling at x miles per hour on dry, level pavement. If a driver can see only 200 feet ahead on a highway with a sharp curve, then safe drivers speed x satisfy the quad inequality 1/2x quantity squared + 11/5x is less than or equal to 200. Solve this inquality to determine safe stopping speeds in a curve where a driver can see the road ahead at most 200 ft. what might be a safe speed limit for this curve?

Answer 1

I cannot determine exactly your first term.

Put the quadratic in this form

ax^2+bx<=200
then
ax^2+bx-200<=0
then solve the left side

x=(-b+-sqrt(b^2-4ac)/2a