Please check the attached photo for reference.
By "how much", I am assuming that you meant distance.
If we look at the diagram closely, we could see that we have two sides enclosing an angle. If this happens, this means that we could use the cosine rule.
Recall, cosine rule: [tex]c^2=a^2+b^2-2ab(cosC)[/tex]
Therefore, we just plug-in all the given values to the formula:
[tex]c^2=600^2+90^2-(2*600*90)cos20[/tex]
Remember: It doesn't matter which of the two distances is a or b.
Using our calculator, we get the value for c^2 as 324027.14 m
Taking it's square root for the value of c, we get 569.23 m.
If you still have problems or if there are errors in my answer, don't hesitate to message me or comment on my profile. Thanks!