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Flura [38]
3 years ago
5

What is the solution to the system of linear equations below? 2/5x−y=6 −2x+5y=−30 Select one: A. (-13, 14) B. (-5, -8) C. no sol

ution D. infinitely many solutions
Mathematics
1 answer:
tester [92]3 years ago
3 0

Answer:

D. Infinitely many solutions

Step-by-step explanation:

-\frac{2}{5}x-y=6      |  -2x+5y=-30

1.Since neither equation contains an isolated. However, we can isolate -y in the first equation by adding \frac{2}{5}x to both sides.

Like this: \frac{2}{5}x-\frac{2}{5}x-y=6-\frac{2}{5}x

ending up with y=6-\frac{2}{5}x

2.Now, we can change y to a positive y. By doing so, we divide -y by the entire equation.

Like this \frac{-y=6-\frac{2}{5}x }{-y}

Ending with y=-6+\frac{2}{5}x

3.Now, we can plug the expression -6+\frac{2}{5}x into the second equation as a substitute for y, and solve for x. Then, we can use x to calculate y.

Like this -2x+5(-6+\frac{2}{5}x)=-30\\ -2x-30+2x=-30\\

4. Since -2x+2x would cancel out and leave -30=-30. This is true because we know -30 equals -30 with no variable in sight.

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At top (acceleration is upward): 
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We are interested in the ratio of weight (gondola reference frame weight to weight when on the ground): 
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Data: 
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Results: 
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