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3 years ago

-3x+4y=7 y=3x-5 I NEED HELP PL Z HELP ME

Mathematics

1 answer:

andrew-mc [135]3 years ago

3 0

$- 3x + 4y = 7 \\ y = 3x - 5$

[Substitute the given value of y into the first equation]

$- 3x + 4 \times (3x - 5) = 7$

[Distribute 4 through the parentheses]

$- 3x + 12x - 20 = 7$

[Collect like terms]

$9x - 20 = 7$

[Move the constant to the right-hand side and change its sign]

$9x = 7 + 20$

[Add the numbers]

$9x = 27$

[Divide both sides of the equation by 9]

$x = 3$

[Substitute the given value of x into the second equation]

$y = 3 \times 3 - 5$

[Multiply the numbers]

$y = 9 - 5$

[Subtract the numbers]

$y = 4$

[The possible solution of the system is the ordered pair (x,y)]

$(x,y)=(3,4)$

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4 years ago

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Dennis_Churaev [7]

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