Answer:
B
Step-by-step explanation:
A
- Harvard university professor
Answer: Each time the pentagon is rotated , it maps back onto itself. There are five values of for which the pentagon maps back onto itself. This is the same as the number of sides of the pentagon.
8x - 9x²y + 7y² - 2x⁴
-2x⁴ - 9x²y + 8x + 7y²
We have

So

The rational term vanishes as <em>x</em> gets arbitrarily large, so we can ignore that term, leaving us with

and this happens if <em>a</em> = 1 and <em>b</em> = -1.
To confirm, we have

as required.