Answer:
And rounded up we have that n=1068
Step-by-step explanation:
For this case we have the following info given:
the margin of error desired
the level of confidence given
The margin of error for the proportion interval is given by this formula:
(a)
the critical value for 95% of confidence is 
We can use as estimator for the population of interest 
. And on this case we have that 
and we are interested in order to find the value of n, if we solve n from equation (a) we got:
(b)
And replacing into equation (b) the values from part a we got:
And rounded up we have that n=1068
1. (2,3)
2. (-1,-1)
3. infinitely many
4. coincident
5. consistent independent, coincident, inconsistent (in that order)
4x - 5y = -12
-x + 5y = 18
Add the equations together:
4x + -x = 3x
-5y + 5y = 0
-12 + 18 = 6
So now you have:
3x = 6
Divide both sides by 3:
X = 2
Now you have the value of x, replace x with 2 in one of the equations and solve for y:
4(2) -5y = -12
8 -5y = -12
Subtract 8 from both sides:
-5y = -20
Divide both sides by -5:
Y = 4
The solution is x = 2 and y = 4 which is written as (2,4)
