How do you solve the following system: $x - 3 y = 20, 7 x + 15 y = 32$ $x-3y=20 , 7x+15y=32$ ?

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Answer 1 · 2018-03-29T12:26:17

$x = 11$ $x=11$
$y = - 3$ $y=-3$

= $x - 3 y = 20$ $x-3y=20$

= $x = 20 + 3 y$ $x=20+3y$ **

Put above in other equation

= $7 (20 + 3 y) + 15 y = 32$ $7(20+3y)+15y=32$

= $140 + 21 y + 15 y = 32$ $140+21y+15y=32$

= $21 y + 15 y = 32 - 140$ $21y+15y=32-140$

= $36 y = - 108$ $36y=-108$

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

Now for $x$ $x$

= $x - 3 (- 3) = 20$ $x-3(-3)=20$

= $x + 9 = 20$ $x+9=20$

= $x = 11$ $x=11$

Hope this helps!

How do you solve the following system: x−3y=20,7x+15y=32x-3y=20 , 7x+15y=32 ?