How do you solve for y $9x + 3y - 5 = 6x - 9y + 10$ ?

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Answer 1 · 2015-10-11T00:00:52

$(5-x)/4$

Your goal here is to isolate $y$ on one side of the equation.

This implies that you need to have all the $x$ -terms and all the integers on the other side of the equation. Your starting equation looks like this

$9x + 3y - 5 = 6x - 9y + 10$

Start by adding $5$ to both sides of the equation

$9x + 3y - color(red)(cancel(color(black)(5))) + color(red)(cancel(color(black)(5))) = 6x - 9y + 10 + 5$

$9x + 3y = 6x - 9y + 15$

Next, add $9y$ to both sides of the equation

$9x + 3y + 9y = 6x - color(red)(cancel(color(black)(9y))) + color(red)(cancel(color(black)(9y))) + 15$

$9x + 12y = 6x + 15$

Next, add $-9x$ to both sides

$color(red)(cancel(color(black)(9x))) - color(red)(cancel(color(black)(9x))) + 12y = 6x - 9x + 15$

$12y = -3x + 15$

Finally, divide both sides by $12$ and simplify where possible

$(color(red)(cancel(color(black)(12)))y)/color(red)(cancel(color(black)(12))) = (-3x + 15)/12$

$y = color(green)((5-x)/4)$

How do you solve for y 9x + 3y - 5 = 6x - 9y + 109x + 3y - 5 = 6x - 9y + 10?