Please help and I need it to be explained

Find the greatest common factor of the polynomial: 10x^5+15x^4-25x^3 10x^5 x^3 5x^3 5

Arestaurant charges $100 to rent its banquet room for an event. it also charges $15 to serve dinner to each guest. write an equation for the total cost of the banquet room in terms of the number of guests. deine your variables. what is the total cost of the banquet room for 20 guests?

Evaluate the discriminant of each equation. tell how many solutions each equation has and whether the solutions are real or imaginary. x^2 - 4x - 5 = 0