Answer:
50
Step-by-step explanation:
add 5 to -25 to get -2/5x by itself.
<span>for that, what you need is a calculator... like say a TI(texas instruments) 83 or 83plus or higher, will do regressions, if you have an android device like a phone or tablet, you can also get an app from the play store "Andie's graph", is a TI calculator emulator, it works just like the calculator itself, you'd only need the ROM
</span><span>that said, you can also use some online calculators for that.
</span>
<span>I could give you a direct link to one, but this site has issues with links, if you do a quick search in google for "keisan exponential regression calculator", it should be the first link, is from the Casio site.
</span>
<span>you could do regressions in a spreadsheet as well.... you could check online for an "addin" or "extension", if you use MS Excel, pretty sure there are some addins for regressions.
</span>
if I recall correctly, Excel does regressions natively, but the addins are just frontends, is all, just some added interfacing.
anyhow, if you have an Android device Andie Graph works peachy, I have an 83plus, 84, 86 in it, they all work just like my old TI83plus.
there's also an app in the play store called Graph89, is an emulator for a TI89, the same you need a tiny little file, and texas instruments provides them, have also, works peachy too.
Total amount of money paid
=11 x 15
=$165
total amount of money sold
=25 x 15
=$375
difference
= 375 - 165
=$210
