Find the value of $v$ such that $\frac{-21-\sqrt{201}}{10}$ a root of $5x^2+21x+v = 0$.
\(\frac{-21-\sqrt{201}}{10}\)
[-21 + sqrt (201) / 10 is also a root
product of the roots = [ (-21)^2 - 201 ] / 100 = 240/100 = 2.4
product of roots = v / 5
v / 5 = 2.4
v = 5 * 2.4 = 12
+760 
