Need fast as possible last year debra had 30,000 to invest how much do she invest each account

Answer
First account = $25,000
second account =$5,000

Explanation
The formular for simple interest is 
Interest = PRT
where P⇒money invested
           R⇒rate
           T⇒ Period (number of years)

Let x to be the money invested in the first account.
Money invested in the second account = 30,000 - x

∴ (x × 0.05×1) + ((30,000-x)×0.07×1) = 1600
0.05x+2100-0.07x = 1600
-0.02x = -500

x = -500/-0.02
   =25,000

Money invested in the first account = $25,000
Money invested in the second account = (30,000-25000) = $5000

Best answer that i found on yahoo ok   set :   x= length of 2nd piece in cm  x- 3= length of 1st piece in cm  x-4= length of 3rd piece in cm  then since you know they all came from the 20 cm ribbon you add them together and set them equal to 20x+ x-3 +x-4 = 20  3x - 7= 20  3x= 27  x= 9  the shortest piece is the third piece which is x- 4  x-4  9-4 = 5  the length of the smallest piece is 5 cm.  the other lengths are  9 cm  6 cm