# Math Help - Linear Equation help

1. ## Linear Equation help

If two lines 6x-y=-5 and ax+2y= 7 are parallel, then a equals?

2. Originally Posted by AltQQ
If two lines 6x-y=-5 and ax+2y= 7 are parallel, then a equals?

Just remember that parallel lines have equal slopes

3. Originally Posted by AltQQ
If two lines 6x-y=-5 and ax+2y= 7 are parallel, then a equals?

If 2 lines are parallel, then they must have the same slope. First rewrite the lines in slope-intercept form:

$y=6x-5$
$y=-\frac{a}{2}x+\frac{7}{2}$

Thus, we can say that $6=-\frac{a}{2} \implies \color{red}\boxed{a=-12}$.

I hope this makes sense!!

4. Omg thanks guys.