Answer:
D
Step-by-step explanation:
The equations are
● 4x + 2y = 10 (1)
● 4x - 2y = -10 (2)
● 4x + 2y = 10
Add - 4x to both sides
● 4x + 2y -4x = 10 -4x
● 2y = 10 -4x
Divide both sides by 2
● 2y/2 = (10 - 4x)/2
● y = 5 - 2x
● y = -2x + 5 (1)
● 4x - 2y = -10
Add -4x to both sides
● 4x -2y -4x = -10 - 4x
● -2y = -10 - 4x
Divide both sides by -2
● -2y/-2 = (-10 -4x)/-2
● y = 10 + 2x
● y = 2x + 5 (2)
So the equation are
● y = 2x + 5
● y = -2x + 5
Graph them
The lines intersect at (0,5) but aren't perpendicular
So the answer is d
Answer:
a)= 2
b) 6.324
c) P= 0.1217
Step-by-step explanation:
a) The mean of the sampling distribution of X`1- X`2 denoted by ux`-x` = u1-u2 is equal to the difference between population means i.e = 2 ( given in the question)
b) The standard deviation of the sampling distribution of X`1- X`2 ( standard error of X`1- X`2) denoted by σ_X`1- X`2 is given by
σ_X`1- X`2 = √σ²/n1 +σ²/n2
Var ( X`1- X`2) = Var X`1 + Var X`2 = σ²/n1 +σ²/n2
so
σ_X`1- X`2 =√20 +20 = 6.324
if the populations are normal the sampling distribution X`1- X`2 , regardless of sample sizes , will be normal with mean u1-u2 and variance σ²/n1 +σ²/n2.
Where as Z is normally distributed with mean zero and unit variance.
If we take X`1- X`2= 0 and u1-u2= 2 and standard deviation of the sampling distribution = 6.324 then
Z= 0-2/ 6.342= -0.31625
P(-0.31625<z<0)= 0.1217
The probability would be 0.1217
Answer:
Step-by-step explanation:
3x=6x-2
Subtract '3x' from both sides
0=3x-2
Add '2' to both sides
2=3x
Divide by 3
x=2/3
If you need the answer in decimal form divide 2 by 3
3/4 + 1/12 = 10/12 and then you simplify it and get 5/6 as your final answer.
Answer:
26 year old
Step by step explanation:
Five years ago, John's age was half of the age he will be in 8 years.
this means that (x-5) = (x+8)/2
-----
solving for x, we get:
2 * (x-5) = x + 8
which becomes:
2x - 10 = x + 8
which becomes:
x = 18
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john is 18 years old now.
5 years ago john was 13
8 years from now john will be 26
13 = 1/2 * 26
