# [SOLVED] An Algebra II Problem: Involving A System of Equations I Think

• Mar 14th 2009, 08:13 AM
stmsnyder1
[SOLVED] An Algebra II Problem: Involving A System of Equations I Think
Hey-

Can someone explain how to do this Algebra II problem?

The top two selling DVDs of 2003 grossed a combined total of $600.9 million. The top selling DVD grossed 39.9 million more than the DVD ranked 2nd. How much did the top selling DVD gross? I know the answer is 320.4 million dollars, but I don't know how the person I got it from, got that answer, so if someone could explain it to me, I would greatly appreciate it. I know the person used an equation, or a system of equations, something like that. -Isabel • Mar 14th 2009, 08:19 AM earboth Quote: Originally Posted by stmsnyder1 Hey- Can someone explain how to do this Algebra II problem? The top two selling DVDs of 2003 grossed a combined total of$600.9 million. The top selling DVD grossed 39.9 million more than the DVD ranked 2nd. How much did the top selling DVD gross?

I know the answer is 320.4 million dollars, but I don't know how the person I got it from, got that answer, so if someone could explain it to me, I would greatly appreciate it. I know the person used an equation, or a system of equations, something like that.

-Isabel

Let x denote the money you get from the top selling DVD and y the amount of money you get from the second from top(?). Then you know:

$x+y=\600.0\cdot 10^6$

$x-\39.9\cdot 10^6 = y$

Plug in the term of y into the first equation:

$x+x-\39.9\cdot 10^6 = \600.0\cdot 10^6$

Solve for x.
• Mar 14th 2009, 10:01 AM
stmsnyder1
Thanks