Answer:
b = ±16
Step-by-step explanation:
Normally to find the number we add to make it a perfect square
We take the coefficient of x
b
Divide by 2
b/2
Then square it
(b/2) ^2
In this case, we are adding 64
(b/2) ^2 = 64
Take the square root of each side
sqrt((b/2) ^2) = sqrt(64)
b/2 = ±8
Multiply each side by 2
b/2*2 = ±8 *2
b = ±16
9 students, 4 are selected and order doesn't matter:
Go to the 9th row of the triangle (mind you the first row is 0), the 2nd is 1st row
9th row: 1 9 36 84 126 126 84 36 9 1
Now choose the 4th column (excluding the 1st , you will get 126 :
so 126 is the number of combination requested:
PROOF: ⁹C₄ = 9!/(9-4)! .4! = (9!)/5!.4! = 126
Answer:
A: Always
B: Sometimes
C: Always
D: Always
E: Always
Step-by-step explanation:
Answer:the answer is all real numbers
Step-by-step explanation: