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
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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
Answer:
y=2x+1
Step-by-step explanation:
First you have to find the slope:
5-1/2 so 4/2 or 2
Then you write it in point-slope: (I used the point (0,1))
y-1=2x
Simplify than:
y=2x+1
Answer: B
Step-by-step explanation:
Answer: (3x + 11y)^2
Demonstration:
The polynomial is a perfect square trinomial, because:
1) √ [9x^2] = 3x
2) √121y^2] = 11y
3) 66xy = 2 *(3x)(11y)
Then it is factored as a square binomial, being the factored expression:
[ 3x + 11y]^2
Now you can verify working backwar, i.e expanding the parenthesis.
Remember that the expansion of a square binomial is:
- square of the first term => (3x)^2 = 9x^2
- double product of first term times second term =>2 (3x)(11y) = 66xy
- square of the second term => (11y)^2 = 121y^2
=> [3x + 11y]^2 = 9x^2 + 66xy + 121y^2, which is the original polynomial.
