Answer:
9x²-30x+25=(3x-5)²
Explanation:
This is a perfect square trinomial.
In general (a±b)² = a²± 2ab +b²
Notice that both 9x² = (3)² and 25 = 5² are perfect squares, so the only question is whether the middle term matches when you square (3x-5), the minus sign being chosen to at result in a negative coefficient for the middle term .
(3x-5)² = (3x)² - 2(3x)(5) +5² = 9x² - 30x + 25
I hope this helps you