Please solve this simple equation

I see...good luck.

x + 0.08x = 37.80

1st step: x(1 + .08) = 37.80

2nd step: x = 37.80 / 1.08

3rd step: x = 35

Clear nuff?

Could mean that 8% tax was charged on a $35 purchase...
 
Denis said:
I see...good luck.

x + 0.08x = 37.80

1st step: x(1 + .08) = 37.80

2nd step: x = 37.80 / 1.08

3rd step: x = 35

Clear nuff?

Could mean that 8% tax was charged on a $35 purchase...

thanks. i wrote that equation myself to figure out how much of the $37.80 was tax.

but im skipping ahead of the books im learning from (i just wanted to try writing a pratical equation). I succeeded in writing the equation in algebra but i couldnt solve it. I dont get what you did in step 1. But im assuming the book im learning from will cover what went on in step one later on in the book (maybe i havent got to it yet). Unless its simple and you can explain it to me quickly?

the way i TRIED to solve it was like this:


x + 0.08x = 37.80
(Divide both sides by 0.08)
x+ x = 472.5
2x = 472.5
(divide both sides by 2)
x= 236.25

this was obviously wrong answer. I see your solution and answer is right. But like i said i dont follow what you did in step 1.
 
einstein said:
x + 0.08x = 37.80
(Divide both sides by 0.08)
x + x = 472.5
No, if you do that, ALL terms must be divided by .08:
x/.08 + x + 472.5 ; so you're no further ahead!

x + 0.08x = 37.80
1st step: x(1 + .08) = 37.80
What I did was simply kinda isolate the x: so it can then be solved for.
If you look at x(1 + .08), this means what's inside brackets is multiplied by what's outside:
x * 1 + x * .08 = x + .08x : OK?

Another example:
32w - 6vw + 7uw ; you can take the "w" out this way: w(32 - 6v + 7u)

Hope that helps...
 
Top