It is still a 45 degree angle.
There are numerous ways to measure angles. See en.wikipedia.org None of these is specific to the metric system.
Sometimes folks find certain problems lend themselves to the use of radians for measuring angles. There are 2Pi radians in a full circle of 360 degrees. (45 degrees)(2Pi radians/360 degrees) = ((2)(45)/360)Pi radians = Pi/4 radians. Pi/4 is approximately 3.14159/4, or .7854 radians.
There are numerous ways to measure angles. See en.wikipedia.org None of these is specific to the metric system.
Sometimes folks find certain problems lend themselves to the use of radians for measuring angles. There are 2Pi radians in a full circle of 360 degrees. (45 degrees)(2Pi radians/360 degrees) = ((2)(45)/360)Pi radians = Pi/4 radians. Pi/4 is approximately 3.14159/4, or .7854 radians.