Find the total minutes:
15 + 30 + 25 + 35 = 105 minutes
This is equal to 1 hour and 45 minutes
Subtract 1 hour and 45 minutes from 9:30
She woke up at 7:45 am
Answer:
So m= - 11
Step-by-step explanation:
* THe vertex is (-2,6), then the equation is y = a(x+2)^2 +6, a is to find out.
* A root is 7 means x=7 and y=0, then :
0 = a(7+2)^2 +6
0=81a+6 or a= -6/81 = -2/27.
* We have the equation: y= -2/27 (x+2)^2 +6=-2/27 [ (x+2)^2-81]
y= -2/27 (x-7)( x+11).
So m= - 11
Hope that you understand.
PART A:
The given quadratic equation is 2x²-10x-8=0
The radicand is given by b²-4ac where a, b, and c are the constants in a quadratic form ax²+bx+c
From the given equation, we have
a = 2
b = -10
c = -8
Radicand b²-4ac = (-10)² - 4(2)(-8) = 100 + 64 = 164
The radicand is >0 hence the quadratic equation has two distinct roots
PART B:
4x²-12x+5 = 0
We can use the factorization method to solve the equation
Firstly, we multiply 4 by 5 to get 20
Then we find the pair of numbers that multiply gives 20 and sum gives -12
The pair of number is -2 and -10
Rewriting the equation
4x²-2x-10x+5 = 0
2x(2x-1)-5(2x-1) = 0
(2x-1)(2x-5) = 0
2x-1 = 0 and 2x-5 = 0
x = 1/2 and x = 5/2
Answer:
The bulbs should be replaced each 1436.9 hours.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean 
and standard deviation 
, the zscore of a measure X is given by:
The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:
How often should the bulbs be replaced so that no more than 1% burn out between replacement periods?
This is the first percentile of hours. So it is X when Z has a pvalue of 0.01.
So it is X when Z = -2.33.
The bulbs should be replaced each 1436.9 hours.
