Answer:
Her error was multiplying -3 and -4 which gives +12 but she wrote -12 instead
Step-by-step explanation:
Mariana workings:
-3(2x - 4) = -12
-6x - 12 = -12
Her error was multiplying -3 and -4 which gives +12 but she wrote -12 instead
-6x = 0
x=0
Correct workings:
-3(2x - 4) = -12
-6x + 12 = - 12
-6x = -12 - 12
-6x = -24
x = -24/-6
x = 4
y - y₁ = m(x - x₁)
y - (-1) = 4[x - (-3)]
y + 1 = 4(x + 3)
y + 1 = 4(x) + 4(3)
y + 1 = 4x + 12
- 1 - 1
y = 4x + 11
The answer is B.
Answer:
(-2,3)
Step-by-step explanation:
For the point to be 2/3 of the way; it means it divides AB into the ratio 2 to 1
Now, we can use the internal section formula to get the coordinates of this point
(x,y) = (nx1 + mx2)/(m + n), (ny1 + my2)/(m + n)
where (m,n) = (2,1)
(x1,y1) = (-4,-1)
(x2,y2) = (5,5)
(x,y) = (1(-4) + 2(-1)/(1+2), (1(-1)+2(5)/(1+2)
(x,y) = (-4-2)/3, (-1 + 10)/3
(x,y) = (-2,3)
Answer:
The 99% confidence interval for the true mean number of reproductions per hour for the bacteria is between 9.6 and 10.
Step-by-step explanation:
We have that to find our
level, that is the subtraction of 1 by the confidence interval divided by 2. So:

Now, we have to find z in the Ztable as such z has a pvalue of
.
So it is z with a pvalue of
, so 
Now, find the margin of error M as such

In which
is the standard deviation of the population and n is the size of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 9.8 - 0.2 = 9.6 reproductions per hour.
The upper end of the interval is the sample mean added to M. So it is 9.8 + 0.2 = 10 reproductions per hour.
The 99% confidence interval for the true mean number of reproductions per hour for the bacteria is between 9.6 and 10.