help someone please

[suxatmath]

Does anyone know how to solve absolute value equations? I know how to graph them. But I can't solve them. Problems like...

3y=|2x-9|

explain it to me please, my head hurts.

 

[Guest]

Umm... Have you checked at purplemath.com? Eliz is absouletly superb at any question. Here's the link to ab. value... http://www.purplemath.com/modules/solveabs.htm

I'm not the greatest with math either. My head is hurting right now too. Otherwise, I'd try to explain it to you...

 

[wjm11]

3y=|2x-9|

Factor out a 2 from the right side so that x has a coefficient of 1:

3y=2*|x-9/2| Now divide both sides by 3 so y is by itself:

y=(2/3)*|x-9/2|

Consider the “parent” (simple) function:

y = |x|

This is a V-shaped graph with vertex at the origin, right? The –9/2 inside the absolute value moves the graph 9/2 in the positive x (right) direction. The 2/3 coefficient outside the absolute value sign changes the shape of the V. Make sense?

 

[dagr8est]

n/m

 

[Corsair_cavalier]

to simply solve absolute values without graphing just remember that since it is absolute value it covers opposites of the equation, therefore you just take the opposite of one side and solve the two equations.

3y=2x-9 and 3y=-2x+9.