How many times does 60 go into 450

What's the difference between: x≥0 and nonnegative integer. ?

Aregular hexagon rotates counterclockwise about its center. it turns through angles greater than 0° and less than or equal to 360°. at how many different angles will the hexagon map onto itself?

How to choose the sign of the radical in the denominator of the formula for the distance from a point to a line.