Answer:
[tex]\large\boxed{B.\ w=-\dfrac{4}{3},\ w=\dfrac{5}{2}}[/tex]
Step-by-step explanation:
[tex]6w^2-7w-20=0\\\\6w^2-15w+8w-20=0\\\\3w(2w-5)+4(2w-5)=0\\\\(2w-5)(3w+4)=0\iff2w-5=0\ \vee\ 3w+4=0\\\\2w-5=0\qquad\text{add 5 to both sides}\\2w=5\qquad\text{divide both sides by 2}\\\boxed{w=\dfrac{5}{2}}\\\\3w+4=0\qquad\text{subtract 4 from both sides}\\3w=-4\qquad\text{divide both sides by 3}\\\boxed{w=-\dfrac{4}{3}}[/tex]
