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URGENT? Topic: How to write a system of equations with 3 variables
June 16, 2019 / By Abinoam
Question: Ok so we learned how to solve the solution of the system using substitution. I don't uderstand it. How would you solve 6y+5x=8 and x+3y=-7. Please show steps and explain thoroughly. Like I really don't get how in the beginning you have to set up an equation using substitution. Please help(:
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Sissie Sissie | 1 day ago
A system means that we know that an x in one equation means the same thing as the x in the other. If we only have one equation that has both an x and a y, it is impossible to know what the values are. There are an infinite number of combinations of x and y variables that can give you the constant on the right hand side of the equation. But with two equations, there will only be one x value and one y value that will be true for both cases. In algebra you can always move things around. a + b = c is that same as a + b - c = 0, and so on. We need to use both equations in order to find which values for x and y will satisfy both equations. So I always look for which variable is the easiest to isolate. In this case, isolating the x of the second equation is the easiest because it does not require any division: 6y + 5x = 8 x = -7 -3y By saying that the right hand side of the 2nd equation is equal to x, we can re-write the first equation using this "definition" of x: 6y + 5(-7 -3y) = 8 Now we have one equation with just one variable. We can solve for y: 6y -35 -15y = 8 -9y = 43 y = -43/9 Now that we have the y value, we can "plug it in" to either of our equations to find x. I will choose th 2nd because it looks easier: x + 3(-43/9) = -7 x - 43/3 = -7 x = 22/3 I hope this makes things slightly more clear. Another way of looking at it is to graph both linear equations. The solution is where the two lines meet. ie the two lines intersect at (22/3, -43/3)
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Sissie Originally Answered: Help? Please? Urgent?
Growing up in a small town setting, my dream has always been to leave for something more exciting. I want to engage in a career that will allow me to travel and offer me many remarkable opportunities that will let me to help others. Keeping these thoughts in mind, while researching schools and majors, I was instantly very attracted to International Relations at the University of California Davis. An International Relations major consists of a large range in its areas of study, including politics, institutions, as well as learning the principles of diplomacy and foreign policy. There are four main areas of focus in International Relations; world trade and development, peace and security, global environment, as well as peoples and nationalities. Try to remove the passive voice; words like "the" "in" and replace them with active words.
Sissie Originally Answered: Help? Please? Urgent?
Can you proof read this and edit? I would shorten some of the sentences and re-write it to make it flow a bit better. I think you're on the right track, but here's how I would write it. "I want to engage in an exciting career that will (leave out essentially) allow me to help others. I have kept this in mind while researching schools and majors. When exploring possibilities at the University of California Davis, I was instantly attracted to the International Relations course of study. I have come to recognize that the International Relations curriculum consists of a broad range of disciplines including the study of politics, institutions, diplomacy and foreign policy. Your last sentence is fine, but you might want to emphasize why you think those four areas are so important. Good Luck
Sissie Originally Answered: Help? Please? Urgent?
i changed some redundancies Growing up in a small town, my dream has always been to leave the area and move onto enticing things. I want to engage in an expandable career that will allow me to travel, and offer remarkable opportunities that lets me help others. Keeping these thoughts in mind while researching schools and majors, I was instantly attracted to International Relations at the University of California Davis. The major of International Relations consists of a broad range of areas of study, which include politics, institutions, learning the principles of diplomacy and foreign policy. The four main areas of focus in International Relations are World Trade and Development, Peace and Security, Global Environment, and Peoples and Nationalities. . .

Phoenix Phoenix
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Phoenix Originally Answered: URGENT?
A system means that we know that an x in one equation means the same thing as the x in the other. If we only have one equation that has both an x and a y, it is impossible to know what the values are. There are an infinite number of combinations of x and y variables that can give you the constant on the right hand side of the equation. But with two equations, there will only be one x value and one y value that will be true for both cases. In algebra you can always move things around. a + b = c is that same as a + b - c = 0, and so on. We need to use both equations in order to find which values for x and y will satisfy both equations. So I always look for which variable is the easiest to isolate. In this case, isolating the x of the second equation is the easiest because it does not require any division: 6y + 5x = 8 x = -7 -3y By saying that the right hand side of the 2nd equation is equal to x, we can re-write the first equation using this "definition" of x: 6y + 5(-7 -3y) = 8 Now we have one equation with just one variable. We can solve for y: 6y -35 -15y = 8 -9y = 43 y = -43/9 Now that we have the y value, we can "plug it in" to either of our equations to find x. I will choose th 2nd because it looks easier: x + 3(-43/9) = -7 x - 43/3 = -7 x = 22/3 I hope this makes things slightly more clear. Another way of looking at it is to graph both linear equations. The solution is where the two lines meet. ie the two lines intersect at (22/3, -43/3)
Phoenix Originally Answered: URGENT?
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