Adding and subtracting Radical expressions show work pls

Answer:
[tex] - 7\sqrt{17} [/tex]
Step-by-step explanation:
honestly, there's not really a step by step tutorial, you just pretend like the square root 17 is x and do exactly like you'd do otherwise. -3x-4x= -7x and the x is square root 17 so you just put it together like that <3