How many ways can you select 3 different toppings for a pizza with 8 toppings to choose from?

Find the value of the cosine for angle a

Me solve this problem, and someone clearly explain to me how to solve it.1.) use the value of the discriminant to determine if the given trinomials has 2 real solutions, 1 real solution, or no real solutions.a.  x2  − 4x  − 7 = 0b. 4r2  + 11r  − 3 = 0c. 3m2  + 7 = 0d.  t2  + 2t  + 1 = 0

If f(x) = 4x - 3 and g(x) = x + 4, find (f - g) (x)