2/9 is the answer hope it will help
Answer:
x=1.25 and y=-5.5
Step-by-step explanation:
2x+y=-8, 2x=-y-8 or 4x=-2y-16. Plug this value in the second equation, we have - 2y-16-2y=6, y=-5.5. Plugging this in any equation we have, x=1.25
Answer:
The last one.
Step-by-step explanation:
The solutions with the horizontal lines are wrong because then h(x) would be -1 and 1 respectively.
The subtlety is in the open or closed dot. x ≥ -1 means that -1 is included, which is drawn as a closed dot. x < -1 means that -1 is excluded, which is drawn as an open dot.
Hence the last graph is the correct one.
Answer:
We have sinθ = 12/13
The method here is to figure out the value of θ
Using a calculator sin^(-1)(12/13) =67.38°
67.38° is in quadrant 1 so we must substract 67.38° from 180° wich is π
- 180-67.38= 112.61° ⇒ θ= 112.61°
Now time to calculate cos2θ and cosθ using a calculator
- cosθ = -5/13
- cos2θ = -0.7
The values we got make sense since θ is in quadrant 2 and 2θ in quadrant 3
Answer:
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.
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 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 0.181 - 0.0140 = 0.167 cc/m³.
The upper end of the interval is the sample mean added to M. So it is 0.181 + 0.0140 = 0.195 cc/m³.
The 90% confidence interval for the population mean iron concentration is between 0.167 cc/m³ and 0.195 cc/m³.