Answer: A
Hope this is helpful.
Step-by-step explanation:
Try to solve using simultaneous equations with each answer given.
x + 2y = 5
x = 5 - 2y
Plug this into each equation
A 2(5 - 2y) + 4y = 3
10 - 4y + 4y = 3
10 = 3 in consistent
B 5(5 - 2y) + 2y = 3
25 - 10 y + 2y = 3
25 - 8y = 3
8y = 22
y = 2.75
Using original equation solve for x
5x + 2(2.75) = 3
5x + 5.5 = 3
5x = -2.5
x = -0.5
Using original equation,
(-0.5) + 2 (2.75) = 5
-0.5 + 5.5 = 5 consistent
C 6x + 12y = 30
6(5 - 2y) + 12y = 30
30 - 12y + 12 y = 30 consistent for every value of y
D 3(5 - 2y) + 4y = 8
15 - 6y + 4y = 8
- 2y = -7
y = 3.5
x = 5 - 2y
x = 5 - 7
x = -2
Solving for x
3(-2) + 4(3.5) = -6 + 14 = 8 consistent
So A is the correct answer
Answer:
(0.88, 0.65)
Step-by-step explanation:
Given that the two equations of the line are:
y =( -2/5)x + 1 and y = 3x – 2. To find the solution, we have to solve the equations simultaneously.
y =( -2/5)x + 1 . . . 1)
y = 3x – 2 . . . 2)
Subtracting equation 1 from equation 2:
3.4x -3 = 0
3.4x = 3
Dividing through by 3.4
3.4x/3.4 = 3/3.4
x = 0.88
To find y, substitute x = 0.88 in equation 2:
y = 3(0.88) - 2
y = 2.65 - 2
y = 0.65
This means that the solution to the system of equations is the point of intersection of the two lines which is at (0.88, 0.65)
Answer:
<u>The length of the longer segment of the 50 cm chord = 40</u>
Step-by-step explanation:
let the length of the longer segment of the 50 cm chord = x
so, the other segment = 50 - x
A chord of 50 cm bisects a chord of 40 cm
using the Intersecting Chords Theorem
so, x(50-x) = 20 * 20
50x - x² = 400
x² - 50x + 400 = 0
(x - 40)(x - 10) = 0
x = 40 or x = 10
<u>So, the the length of the longer segment of the 50 cm chord = 40</u>
Answer:
We can conclude that the battery life is greater than the 32 hour claim.
Step-by-step explanation:
The null hypothesis is:
The alternate hypotesis is:
Our test statistic is:
In which X is the statistic, 
is the mean, 
is the standard deviation and n is the size of the sample.
In this problem, we have that:
So
We need to find the probability of finding a mean time greater than 37.8. If it is 5% of smaller(alpha = 0.05.), we can conclude that the battery life is greater than the 32 hour claim.
Probability of finding a mean time greater than 37.8
1 subtracted by the pvalue of z = t = 2.46.
z = 2.46 has a pvalue of 0.9931
1 - 0.9931 = 0.0069 < 0.05
So we can conclude that the battery life is greater than the 32 hour claim.
Answer:
<em>Statistical inference</em>
Step-by-step explanation:
The confidence interval is used to give a range of values for a target population while applying the law of probability. Inferential statistics makes use of data obtained from a given population to predict and make a conclusion on a study.
Statistical inference is the process of applying the tools for inferential statistics to analyze data gotten from a given fraction of the population. This process is based on probability and random sampling.
<em>When a confidence interval is used to conclude a population study, it is certainly based on probability. Therefore the correct option is statistical inference. </em>
