5 cool math tricks ft. Technicality

Regarding the square root trick, there is a similar trick where you can calculate the complex result from raising any complex number to real power. 
Lets take 
(2+5i)^3.5 as an example, but this will work with any number. (so long as it's not raised to a complex power

Construct your right triangle with a length of 2 units and a height of 5 units. 
now you may want to tape it down. you are going to imagine a coordinate system where the verticy made by the hypotenuse and the length is point (0,0) 
define it so your length is parallel to the x axis, and the height is parallel to the y axis. (technically its the real and imaginary axis, but it doesnt matter) 

Now, using a protractor measure the angle of the point at your origin (0,0) 
multiply this angle by your power in this case multiply by 3.5, then using this new angle draw a line going out from there. 

now measure the length of your hypotenuse.  You need to take that length and raise it to 3.5 
You can do this by taking its square root using the methods shown in this video, then raise its square root to the 7th power. 
Now your almost done. starting from the origin, Draw a line with that angle you calculated earlier, to have a side length equal to the result of raising the hypotenuse to 3.5 

Now all you need to do is from the end point of the line you drew find its coordinate. 
Measure how much below or above the horizontal origin it is. you should fine, its roughly 310 units bellow. 
Then measure how far left or right it is from the vertical origine line. And you should find it roughly 188 units to the left. 
You now have your answer. 
(-188-310i)