Multiply -3/11 and -2/15 straight across
-3(-2) = 6
11(15) = 165
6/165 is your product, or 0.036 (rounded)
hope this helps
X^2 - 8x = (x - 4)^2 - 16
we add 16 to give x^2 - 8x + 16 which is a perfect square
x^2 - 8x + 16 = (x - 4)^2
answer is 16
Triangular sequence = n(n + 1)/2
If 630 is a triangular number, then:
n(n + 1)/2 = 630
Then n should be a positive whole number if 630 is a triangular number.
n(n + 1)/2 = 630
n(n + 1) = 2*630
n(n + 1) = 1260
n² + n = 1260
n² + n - 1260 = 0
By trial an error note that 1260 = 35 * 36
n² + n - 1260 = 0
Replace n with 36n - 35n
n² + 36n - 35n - 1260 = 0
n(n + 36) - 35(n + 36) = 0
(n + 36)(n - 35) = 0
n + 36 = 0 or n - 35 = 0
n = 0 - 36, or n = 0 + 35
n = -36, or 35
n can not be negative.
n = 35 is valid.
Since n is a positive whole number, that means 630 is a triangular number.
So the answer is True.
Answer:
option C.
Step-by-step explanation:
The given graph is the bell shaped graph.
From the graph we can observe that the peak is at 69.
So, the mean of the data is = 69 .
Standard deviation is the deviation of the graph from the mean value.
= 72-69 = 3
Hence, the standard deviation is equal to 3.
So, the correct answer is option C.
