Answer:
52.4
Step-by-step explanation:
40 hundredths as a decimal is 40/100 which is .40.
The "fifty two" is a whole number which is in front of the ".40" which makes 52.4 or 52.40.
There are 9 whole numbers in between 20 and 30
Distribution method
(2x+6)(2x-6)
=4x^2-12x+12x-36
=4x^2-36