Respuesta :

Answer:

www.symbolab.com , its a easy algebra calculator. wish u luck

Step-by-step explanation:

(2y-9x)²
(2y-9)(2y-9)
the equation is ² so break it
into two bracket

4y²-18y -18y+81 multiply it out
=4y² - 36y + 81 (the answer)

I assume this would be the correct answer but you could simplify further