For this case we have the following polynomial:

To solve the problem we apply the following steps:
1) We make a change of variables u = x ^ 2
2) We rewrite the polynomial
3) Solve the quadratic equation using the formula for the quadratic equation
4) We return the change and find four roots
Answer:
See attached image for procedure and solution
AB = -2
CD = -1
BC = -3/-2
AD = -2/-3
27 millimeters multiplied by 1 cm/10 mm= 2.7 centimeters