Answer:
(1/2,4)
Step-by-step explanation:
First, determine y in first equation: 2x+y=5 or y=5-2x
replace value of y determined in first equation (5-2x) into 2nd equation
4x-3(5-2x)=-10
4x-15+6x=10
10x=5
x=1/2
put value of x into either equation to solve for y so
2(1/2)+y=5
1+y=5
y=4
answer: x=1/2, y=4
check answer by substituting x and y into either equation:
4x-3y=-10
4(1/2)-3(4)=-10
2-12=-10
-10=-10
or
2x+y=5
2(1/2)+4=5
1+4=5
5=5
Answer:
a) 
With:


b) 

c) 

d) 


Step-by-step explanation:
For this case we know the following propoertis for the random variable X

We select a sample size of n = 81
Part a
Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

With:


Part b
We want this probability:

We can use the z score formula given by:

And if we find the z score for 89 we got:


Part c

We can use the z score formula given by:

And if we find the z score for 75.65 we got:


Part d
We want this probability:

We find the z scores:



Answer:
23
Step-by-step explanation:
5x6-c
5x6=30
30-c
c=7
30-7=23
Answer:
I had x to be 2
Step-by-step explanation:
a square has all it side to be equal
so 10x=6x+8
you will group like terms 10x-6x=8
4x=8 you divide both side by the coefficient of x which is four so X=2