How to determine unknown value from an equation

Power_roadatmaxspeed=((2.73*C_r*m)+(0.0126*C_d*a*S^2))*S

The above written is my equation. I have given values for C_r, m ,C_d , a initially as they are given data of a vehicle .I found the Power_roadatmaxspeed now. So I want to find S. How to determine through matlab ?

Answer 1

[Matt J]

It's a cubic polynomial, so you can use roots().

[Walter Roberson]

roots([0.0126*C_d*a, 0, 2.73*C_r*m, -Power_roadatmaxspeed ])

[Vinay Srinivasan]

Thank you so much