Step-by-step explanation:
Recall the identity
We can see that
The output should be -5+10=5
Answer:
120
Step-by-step explanation:
If order doesn't matter, there are 10 ways to chose the first ride, 9 ways to choose the second, and 8 ways to choose the third. This product (720) has you riding the same 3 coasters in 6 different orders. Dividing by 6 gives ...
720/6 = 120 different combinations of roller coasters
_____
This number might be written as 10C3 (choose 3 from 10). The meaning of that notation is ...
nCk = n!/(k!(n-k)!)
10C3 = 10!/(3!·7!) = 10·9·8/(3·2·1) = 120
<span>7x - 5y =21
-7 -7
5y = 14
---- -----
5 5
y= 2.8
(4,2.8)</span>
