we have that
V(-2,-1) and U(-3,-4)
step 1
Find out the angle of the vector V with the x-axis
Let
x1 ----> angle of vector V with the x-axis
tan(x1)=1/2
x1=tan^-1(1/2)
x1=26.6 degrees
step 2
Find out the angle of the vector U with the x-axis
Let
x2 ----> angle of the vector U with the x-axis
tan(x2)=4/3
x2=tan^-1(4/3)
x2=53.1 degrees
step 3
Find out the angle between the two vectors
x2-x1=53.1-26.6=26.5 degrees
therefore
The angle between the two vectors is 26.5 degrees