Answer:
455 or 680, depending
Step-by-step explanation:
If we assume the three choices are different, then there are ...
15C3 = 15·14·13/(3·2·1) = 35·13 = 455
ways to make the pizza.
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If two or three of the topping choices can be the same, then there are an additional ...
2(15C2) +15C1 = 2·105 +15 = 225
ways to make the pizza, for a total of ...
455 + 225 = 680
different types of pizza.
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There is a factor of 2 attached to the number of choices of 2 toppings, because you can have double anchovies and tomato, or double tomato and anchovies, for example, when your choice of two toppings is anchovies and tomato.
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nCk = n!/(k!(n-k)!)
I believe the answer is B and E
9x-8=9x-3/2 X3
9x-8=27x-9/2
2(9x-2)=27x-9
18x-4 =27x-9
18x-27x=-9+4
-9x =-5
9x=5
X=5/9 answer
[-½, ¾]; use either "Substitution" or "Elimination" to do this, and you'll see that this answer is correct.
