How do you solve the following system: $x + 2 y = 9, 7 x + 15 y = 32$ $x + 2y = 9 , 7x+15y=32$ ?

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Answer 1 · 2016-01-05T20:35:34

The system is

$x + 2 y = 9$ $x+2y=9$ (1)

$7 x + 15 y = 32$ $7x+15y=32$ (2)

Multiply the first equation by $- 7$ $-7$ and add to the second you get

$(- 7) x - 14 y + 7 x + 15 y = - 63 + 32 \Rightarrow y = - 31$ $(-7)x-14y+7x+15y=-63+32=>y=-31$

hence $x = 9 + 2 \cdot 31 = 72$ $x=9+2*31=72$

The solution is $(x, y)$ $(x,y)$ = $(72, - 31)$ $(72,-31)$

How do you solve the following system: x+2y=9,7x+15y=32x + 2y = 9 , 7x+15y=32 ?