Answer:
x = 25.35 (or 2129/84) and y = 4334.04 (or 121353/28)
Step-by-step explanation:
The given equations are set up and ready to go with substitution. Simply just plug in the first equation to the second equation as both are equal to y.
Step 1: Replace y in <em>y = 87x + 2129 </em>with <em>171x</em>
171x = 87x + 2129
Step 2: Subtract 87 x on both sides
84x = 2129
Step 3: Divide both sides by 84 to get x
x = 2129/84 or 25.35 (rounded)
To get y, simply plug in x into one of the 2 original equations. In this case, I will use the first equation:
y = 171 (25.35)
y = 121353/28 or 4334.04 (rounded)
You can check your work by plugging both solutions into the calculator and see if they equal each other. The values for these answers are solely based on the equations, so if you write the <em>equations </em>wrong themselves, then that means you have the values wrong as well.
Answer:
a plane is formed by two rays with the same end point
Answer:
And we can find this probability with the complement rule:
Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the average homicide rate for the cities of a population, and for this case we know the distribution for X is given by:
Where
and
We are interested on this probability
And the best way to solve this problem is using the normal standard distribution and the z score given by:
If we apply this formula to our probability we got this:
And we can find this probability with the complement rule: