How do you solve using elimination of $5x+4y+2=0$ and $4x-5y-23=0$ ?

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Answer 1 · 2018-03-08T14:21:58

$x=2$
$y=-3$

$5x+4y+2=0$

$=> 5x+4y=-2$

Multiply 5 both sides

$=> 25x+20y=-10$ ----(1)

$4x-5y-23=0$

$=>4x-5y=23$ ----(2)

Multiply 4 both sides

$=>16x-20y=92$ ----(3)

$(1) + (3)$

$=> 25x+20y+16x-20y=-10+92$

$=> 41x=82$

$=> x=2$

Put this value in $(2)$

$=> 4(2)-5y=23$

$=> 8-5y=23$

$=> 8-23=5y$

$=> -15=5y$

$=> -3=y$

How do you solve using elimination of 5x+4y+2=0 5x+4y+2=0 and 4x-5y-23=04x-5y-23=0?