I will use bold v, u, and w to denote vectors, and
notation like to denote components of a vector (here x component of vector u)
Hopefully it renders properly.
u = 2i - 3j (1)
From v || u: v = 2ci-3cj (2)
where c is some scaler value.
From w perpendicular to u: w∙u = 0
which translates to
2 - 3 = 0 (3)
We also want: w + v = 4i + 4j (4)
(3) ==>
Now we can write, using (3) and (4):
(5) 2c + = 4
{6) -3c + = 4
Solving this for c gives which tells us via (2)
that v = (-8/13)i + (12/13)j
Now you can use (5) and (6) to solve for or plug c into
(4) and solve for and (I did it the latter way):
w = (60/13)i + (40/13)j
Check:
I checked everything but you should do so as an exercise.
1. Check that w + v = 4i + 4j
2. Check that w∙u = 0 ()
3. Check that |v∙u| = |v||u|