I'm going to assume that the ' 7.51 ' is the angle expressed in radians.
So this is just like any other unit conversion exercise.
You know that 180 degrees = pi radians.
Divide each side by pi radians, and you have
180 degrees / pi radians = 1 .
Great ! Now take the angle you have ... 7.51 radians ...
and multiply it by ' 1 '.
(7.51 radians) x (180 degrees / pi radians) =
(7.51 x 180 / pi) degrees = 430.29 degrees
As you ( I ) worked through this problem, a very useful number
fell out . . . It's 180/pi = 57.296 , or just 57.3 is close enough.
Here's how you can use that number:
-- 1 radian = 57.3 degrees
-- 1 degree = 1/57.3 of a radian
-- Got some radians ? Multiply by 57.3 to get degrees.
-- Got some degrees ? Divide by 57.3 to get radians.