P² - 12 p - 13 = 0
Δ = ( -12)² - 4 ( 1 * - 13)
Δ = 144 + 52
Δ = 196 = 14²
x₁ = (- ( -12) + 14 ) / 2 = 26/2 = 13
x₂ = ( - ( -12) - 14) /2 = - 2 /2 = - 1
S = 13
Answer:
-2x=30y-6
2x+30y-6=0
Step-by-step explanation:
Answer:
Not possible to work out
Step-by-step explanation:
NO Explanation can be explained as this question cannot be solved
Answer:
The proportion of students whose height are lower than Darnell's height is 71.57%
Step-by-step explanation:
The complete question is:
A set of middle school student heights are normally distributed with a mean of 150 centimeters and a standard deviation of 20 centimeters. Darnel is a middle school student with a height of 161.4cm.
What proportion of proportion of students height are lower than Darnell's height.
Answer:
We first calculate the z-score corresponding to Darnell's height using:

We substitute x=161.4 ,
, and
to get:

From the normal distribution table, we read 0.5 under 7.
The corresponding area is 0.7157
Therefore the proportion of students whose height are lower than Darnell's height is 71.57%