Question

Help on both 5 and 6 please.

Answer 1

5] The resultant vector will be:
<-6,5> and <6,-5>
=<(-6+6),(5-5)>
=<0,0>
the resultant vector is <0,0>


6] The value of x will be found as follows
tan θ=(opposite)/(adjacent)
θ=20°
hence:
tan 20=x/15
x=15tan20
x=5.4595~5.5 yd

Answer 2

Question 5.
To get the resultant of two vectors we add the two vectors given. 
In this case, <-6,5> and <6,-5> 
Therefore, <(-6+6), (5+-5)>
                  = <0,0>

Question 6
The appropriate trigonometric ratio to use in the question is tan
Tan θ = opposite/ adjacent
θ is 70 degrees ( 90-20)
Opposite is 15 yd 
Adjacent is x
Therefore;
               Tan 70 = 15/x
                        x = 15/tan 70
                        x = 5.45955
                          ≈ 5.5 yd
Thus, the value of x (nearest tenth) is 5.5 yd