How do you solve the following system?: $- x + 5 y = 7, x = - 3 x + 4 y - 17$ $-x+5y=7 , x=-3x + 4y-17$

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Answer 1 · 2016-01-01T12:37:47

$x = - 9.5, y = - 0.5$ $x=-9.5, y=-0.5$

$- x + 5 y = 7$ $-x+5y=7$

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

$x = - 3 x + 4 y - 17$ $x=-3x+4y-17$

$2 x - 4 y = - 17$ $2x-4y=-17$ --- $(2)$ $(2)$

Subsitute $(1)$ $(1)$ into $(2) :$ $(2):$

$2 (5 y - 7) - 4 y = - 17$ $2(5y-7)-4y=-17$

$10 y - 14 - 4 y = - 17$ $10y-14-4y=-17$

$6 y = 14 - 17$ $6y=14-17$

$6 y = - 3$ $6y=-3$

$y = - 0.5$ $y=-0.5$

Subsitute $y = - 0.5$ $y=-0.5$ into $(1)$ $(1)$ :

$x = 5 (- 0.5) - 7$ $x=5(-0.5)-7$

$x = - 2.5 - 7$ $x=-2.5-7$

$x = - 9.5$ $x=-9.5$

x=-9.5, y=-0.5

How do you solve the following system?: −x+5y=7,x=−3x+4y−17 -x+5y=7 , x=-3x + 4y-17