Basically just move the decimal place to the left until your front number is in the ones place. Then, however many places you move the decimal point over is what power you'll raise 10 to. I haven't done it in a while but I think that's how you do it
When it comes to rotations by 90 degrees or 270 degrees, you just have to switch the order of x- and y- coordinates. Then find the sign by considering which quadrant will it be. In this case, it is originally on the positive y-axis and now it would be +ve x-axis.
