Four times the sum of a number and two increased by three is at least twenty seven

I’m really confused and need your assist me with this question i’ve never been taught

Astrid spent $36 on new shoes. this was $12 less than twice what she spent on a new skirt. part a: which equation would solve for how much she spent on the skirt? part b: solve the equation in the workspace provided below. how much did astrid spend on her skirt?

Find the derivative of the function