900,000 because that is where the value of 9 is placed in the number.
Work is provided in the image attached.
24! 2 plus 4 is 6 and 6 times 4 for the scale factor
The expression 36x² - 121 is in the 'difference of two squares form' which is (a² - b²)
Factorising (a² - b²) gives (a+b)(a-b)
Factorising 36x² - 121 gives (6x+11)(6x-11)