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3 years ago

Solving by elimination 5x+2y= -3 3x+3y=9 please help me solve x and y

1 answer:

6 0

1) -3(5x+2y=-3)⇒ -15x-6y=9
⇒ -9x=27
2(3x+3y=9)⇒ 6x+6y=18

2) -9x/-9=27/-9 ⇒ x=-3

3) 3(-3)+3y=9⇒ -9+9+3y=9+9⇒ 3y/3=18/3⇒ y=6

Answer: (-3,6)

Reasoning:
Step 1) In order to eliminate, first I had to multiple the first equation by -3 and the second by 2 so that when combining the equations y would cancel each other out so that I could solve for x. <em>Note: There are many combinations as to how you could multiple the equations so that either the x or y would cancel out.
</em>
Step 2) Once y is eliminated, solve for x.

Step 3) Now plug x back into one of the original equations and solve for y. <em>Note: Plug x back into one of the original equations, not the equations that were changed by multiplication,</em>

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Manny does not eat 4/9 of his orange at lunch. Josh does not 5/9 of his orange at lunch. How much orange do Manny and Josh have

olga55 [171]

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<h3>What are fractions?</h3>

A fraction is a non-integer. A fraction usually has a numerator and a denominator. The numerator is the number above. While the denominator is the number below

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Oranges Manny has left = 1 - 4/9 = 5/9

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To learn more about subtraction of fractions, please check: brainly.com/question/915789

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2 years ago

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Korvikt [17]

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3 years ago

The dataset Restaurant Tips contains data recorded from 157 restaurant bills at a bistro in New York over a two week period and

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Step-by-step explanation:

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3 years ago

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Daniel [21]

Answer:

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Step-by-step explanation:

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y = (y2 -y1)/(x2 -x1)(x -x1) +y1

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y = (10.50/6)(x -2) +15.50 . . . . . . . . . . . . simplify a bit

y = 1.75x -3.50 +15.50 . . . . . . simplify more

In the above, we have x = number of books; y = cost. We can use "n" and "C" for those, respectively, as in the equation for Library 1. Then the monthly cost for Library 2 is ...

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3 years ago

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gavmur [86]

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Step-by-step explanation:

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3 years ago

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