If you are adding a positive number to negative number. You are just bringing the negative number closer to zero, if not above zero.
Examples:
-1+1=0
-2+1=-1
-3+1=-2
-4+1=-3
Decompose each velocity in its i and j - coordinates.
1) River's velocity
3.5 m/s, west fo east = 3.5i + 0j
2) Luke's velocity
5m/s, 60° east of north
5* sin(60°) i + 5*cos(60°) j = 4.33 i + 2.5 j
3) Resultant velocity
[3.5i + 0j] + [4.33i + 2.5j] = 7.83i + 2.5j
resultant speed = √[ (7.83)^2 + (2.5)^2 ] = 8.22 m/s
angle = arctan(2.5 / 7.83) = 17.7° north of east (equal to 72.3° east of north).
I hope this helps. Good Luck!
-8 + k = -17
k = -17 + 8
k = 8 -17
k = -9
The complex solutions come in pairs and the only difference between them is the sign between the real and imaginary part, so one of the other two solutions is
. The third solution can be easily found using the rational root theorem, and it's equal to -1.
