The answer would be -21.6
To solve this system by substitution, we must substitute in the value we are given for x in terms of y (the first equation) into the second equation. This is modeled below:
x = -8y - 15
2x + 5y = -8
2 (-8y - 15) + 5y = -8
Now, we should solve this new equation for y. To begin, we should use the distributive property to get rid of the parentheses on the left side of the equation and begin the simplification process.
-16y - 30 + 5y = -8
Next, we can combine like terms on the left side of the equation by adding together the two terms that both contain the variable y.
-11y - 30 = -8
Next, we should add 30 to both sides in order to move all of the constant (number) terms to the left side of the equation.
-11y = 22
After that, we should divide both sides of the equation by -11 in order to get the variable y alone.
y = -2
Now, we can substitute our value for y back into one of our original equations (it doesn't matter which one you choose; they will yield the same answer).
x = -8y - 15
x = -8(-2) - 15
To simplify, we should following the order of operations outlined by PEMDAS and compute the multiplication and then the subtraction.
x = 16 - 15
x = 1
Therefore, the answer to the system is x = 1 and y = -2, or (1,-2) when written as an ordered pair.
Hope this helps!
Essentially, you can always tell a thing's position by 3 coordinates. We also say that our world is three-dimentional: it has three dimensions -that's why three coordinates are needed. If something is on a flat surface, you know its one coordinate (all points on the same surface have the same coordinate) so you only need two more (you can call them vertical and horizontal)
It should be noted that the z score for Thomas test grade is 0.237.
<h3>How to illustrate the information?</h3>
From the information, Thomas took a test in Social Studies and earned a 74.8 and there is the fact that all the students' test grades in the Social Studies class had a mean of 72.6 and a standard deviation of 9.3,
Therefore, the z score for Thomas test grade will be:
= Test score - Mean / Standard deviation
= 74.8 - 72.6 / 9.3
= 0.237.
Therefore, it should be noted that the z score for Thomas test grade is 0.237.
Learn more about standard deviation on:
brainly.com/question/12402189
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Thomas and Pablo began arguing about who did better on their tests, but they couldn't decide who did better given that they took different tests. Thomas took a test in Social Studies and earned a 74.8, and Pablo took a test in Science and earned a 64.1. Use the fact that all the students' test grades in the Social Studies class had a mean of 72.6 and a standard deviation of 9.3, and all the students' test grades in Science had a mean of 61.1 and a standard deviation of 9.8 to answer the following questions.
Calculate the z score for Thomas test grade.
