How do u simplify 12 8/5

Astudent simplified a rational expression as shown.

Draw a tape diagram to represent each situation. for some of the situations, you need to decide what to represent with a variable andre bakes 9 pans of brownies. he donates 7 pans to the school bake sale and keeps the rest to divide equally among his class of 30 students

What is the expression in factored form? -x^2 + 3x + 28 a. (x-7)(x-4) b. -(x-7)(x+4) c. (x+4)(x+7) d. -(x-4)(x+7)