How do you solve the system $y = 2 x - 5 and 4 x - y = 7$ $y=2x-5 and 4x-y=7$ ?

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Answer 1 · 2015-11-16T09:51:32

$x = 1$ $x=1$
$y = - 3$ $y=-3$

Given -

$y = 2 x - 5$ $y=2x-5$ -------------------(1)
$4 x - y = 7$ $4x-y=7$ -----------------------(2)

Substitute $y = 2 x - 5$ $y=2x-5$ in equation (2)

$4 x - (2 x - 5) = 7$ $4x-(2x-5)=7$
$4 x - 2 x + 5 = 7$ $4x-2x+5=7$
$2 x = 7 - 5 = 2$ $2x=7-5=2$
$x = \frac{2}{2} = 1$ $x=2/2=1$
$x = 1$ $x=1$

Substitute $x = 1$ $x=1$ in equation (1)

$y = 2 (1) - 5 = 2 - 5 = - 3$ $y=2(1)-5=2-5=-3$

$y = - 3$ $y=-3$

How do you solve the system y=2x−5and4x−y=7y=2x-5 and 4x-y=7?