Answer:
57.99 degrees
Explanation:
a = <9, 0> and b = <5, 8>.
Then the dot product is (9)(5) + (0)(8) = 45 (a scalar)
The cosine of the angle between these two vectors is
a · b 45 45 5
cos Ф = --------- = ------------------------ = ------------- = -------- = 0.53
|a||b| (9)( √[25 + 64] ) 9(√89) √89
The angle between the vectors is arccos 0.53, which comes out to 1.01 radian or 57.99 degrees.