X(21-18+28y). axis the greatest common factor
-1299 hope it's good enough
60*80-10*16 if it's regular area and not surface area
Answer:

Step-by-step explanation:
Let be
, this expression is simplified by algebraic and trascendental means. As first step, the second order polynomial is simplified. Its roots are determined by the Quadratic Formula, that is to say:


The polynomial in factorized form is:

The function can be rewritten and simplified as follows:
![f(x,y) = \log_{4} [(x-5-\sqrt{25-6\cdot y})\cdot (x-5+\sqrt{25-6\cdot y})]](https://tex.z-dn.net/?f=f%28x%2Cy%29%20%3D%20%5Clog_%7B4%7D%20%5B%28x-5-%5Csqrt%7B25-6%5Ccdot%20y%7D%29%5Ccdot%20%28x-5%2B%5Csqrt%7B25-6%5Ccdot%20y%7D%29%5D)

All I know is that it is not a function it is okay for the domain x to repeat but not the y