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2 years ago

12. If 3x + 4y = -1 and x - 2y = 3, then y=

Mathematics

1 answer:

Hatshy [7]2 years ago

6 0

y=3 and x= 5

Step-by-step explanation:

3×+×=-1 and 4y-2y=3
4×=1 and 2y=3
×=4-1 and y=3+2
x=3 and y=5

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If I have 10 crates of beer each with 12 bottles inside, selling each for R19.00 (South African currency Rand), how much money w

lakkis [162]

Answer: R2280

Step-by-step explanation:

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8 0

1 year ago

Read 2 more answers

A mistake was made in mixing the lemonade—<br> PLEASE HELP!!

beks73 [17]

Answer:

Part A:

$4 + x = y$

$0.5*4 + 1*x = 0.7*y$

$x = 8/3\ quarts\ of\ 100\%\ solution$

$y = 20/3\ quarts\ of\ 70\%\ solution$

Part B:

$x + y = 10$

$2x + 3y = 23$

$x = 7$ and $y = 3$

Step-by-step explanation:

Part A:

The inicial concentration of the lemonade is 50%, and the volume is 4 quarts, and we will add x quarts of a lemonade with a concentration of 100%, so the total volume will be y, and the concentration will be 0.7, so we have that:

$4 + x = y$

$0.5*4 + 1*x = 0.7*y$

Using the value of y from the first equation in the second one, we have:

$2 + x = 0.7*(4 + x)$

$2 + x = 2.8 + 0.7x$

$0.3x = 0.8$

$x = 8/3\ quarts$

$y = 4 + 8/3 = 20/3\ quarts$

Part B:

If he shoots a total of ten targets, we can write the equation:

$x + y = 10$

Each stationary target is 2 points, and each moving target is 3 points, so if the total points is 23, we have:

$2x + 3y = 23$

If we subtract the second equation by two times the first one, we have:

$2x + 3y - 2*(x + y) = 23 - 2*10$

$2x + 3y - 2x - 2y = 23 - 20$

$y = 3$

$x + 3 = 10$ ⇒ $x = 7$

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2 years ago

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Ede4ka [16]

Answer:23

Step-by-step explanation:

92/4

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2 years ago

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musickatia [10]

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3 years ago

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Gnoma [55]

I think you forgot to add the other part of the question

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2 years ago