When asked to factor the trinominal 9x^2+12x+4 a student gives the answer (3x-2)(3x-2) what is one thing wrong with this answer

Apatient is given 50 mg dose of medicine the medicines effectiveness decreases every hour at a constant rate of 40% what is the exponential decay function that models this scenario how much medicine will be left in the patients system after 2 hours

Ijust need to see how to do this. so you don’t have to answer all of them just a step by step explanation of one.

Sandy is upgrading her internet service. fast internet charges $20 for installation and $52.45 per month. quick internet has free installation but charges $57.45 per month. part 1 out of 2 complete the equation that can be used to find the number of months after which the internet service would cost the same. use the variable x to represent the number of months of internet service purchased.