The equation for standard deviation is finding the mean of the numbers, subtracting each of the initial numbers by the mean, squaring each of the results, finding the mean of these results added together, then finding out the square root of the results added together.
The mean of 175 and 165 is 170, subtract 175 and 165 by 170, and you get 5 and -5 respectively. Then, square the results and you get 25 and 25.
Add the two numbers together (25 & 25) then find the square root of it, which is <span>7.07106781187, simplified to 7.07.</span>
Answer:
x = -
, x = 
Step-by-step explanation:
to find the points of intersection equate the 2 equations , that is
7x - 15 = 10 + 12x - 6x² ( subtract 10 + 12x - 6x² from both sides )
6x² - 5x - 25 = 0 ← factor the quadratic on left side
consider the factors of the product of the coefficient of the x² term and the constant term which sum to give the coefficient of the x- term
product = 6 × - 25 = - 150 and sum = - 5
the factors are - 15 and + 10
use these factors to split the x- term
6x² - 15x + 10x - 25 = 0 ( factor the first/second and third/fourth terms )
3x(2x - 5) + 5(2x - 5) = 0 ← factor out (2x - 5) from each term
(2x - 5)(3x + 5) = 0
equate each factor to zero and solve for x
3x + 5 = 0 ⇒ 3x = - 5 ⇒ x = - 
2x - 5 = 0 ⇒ 2x = 5 ⇒ x = 
The slope would have to be -3