How do you solve the system 4x-5y=-43 , 6x+71=y?

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Answer 1 · 2017-06-27T14:15:03

$x = 12 and y = 143$

Equate your $y$ value to the first equation.*

Cancel out $5y$ and find the value of $x$

Substitute the value for $x$ into either of the two equations and solve for $y$

Transpose $4x - 5y = -43" "$ into $" "5y = 4x + 43$
Multiply the second equation, $" "y = 6x + 71" "$ by $" "5$ to get:

$5y = 30x+355$

*You'll end up with two equations:

$5y = 4x + 43$
And
$5y = 30x + 355$

Thus,
$4x + 43 = 30x + 355$

Transpose your variables and constants and you'll get:

$30x - 4x = 355 - 43$

$26x = 312$

$x = 312/26$

$x = 12$

Solve for $y$ since $x = 12,$

Use either of the two equations given, I'll use $y = 6x + 71$

$y = (6 x 12) + 71$

$y = 143$

$x = 12 and y = 143$