How do you solve the following system?: $7x -3y =11, -9x -24y = -7$

Question

2459 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-06-24T15:22:52

$x=19/13$ and $y=-10/39$

$8*(7x-3y)-(-9x-24y)=8*11-(-7)$

$56x-24y+9x+24y=88+7$

$65x=95$ , so $x=95/65=19/13$

Thus,

$7*19/13-3y=11$

$133/13-3y=11$

$-3y=10/13$ or $y=-10/39$

Answer 2 · 2018-06-24T15:24:58

$x=19/13,y=-10/39$

Multiplying the first equation by $-8$ and adding to the second we get

$-65x=-95$
so
$x=95/65=19/13$
plugging this in the first equation we get

$7*19/13-3y=11$
$133/13-11=3y$

$(133-143)/13=3y$

$-10/13=3y$

so

$y=-10/39$

How do you solve the following system?: 7x -3y =11, -9x -24y = -77x -3y =11, -9x -24y = -7