Factorise completely

a). 3xy - 9x

b). x² - 4

c). 2x² + 5y + 1​

a) 3x(y-3)

b) (x-2)(X+2)

Step-by-step explanation:

See the steps below:) You can also use the app photo math, you take a picture and it will give you the answer and explain the steps:)

fahrenheit

step-by-step explanation:

fahrenheit is more precise than celsius. the ambient temperature on most of the inhabited world ranges from -20 degrees fahrenheit to 110 degrees fahrenheit—a 130-degree range. on the celsius scale, that range is from -28.8 degrees to 43.3 degrees—a 72.1-degree range. this means that you can get a more exact measurement of the air temperature using fahrenheit because it uses almost twice the scale.