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