Answer
${{\$}} 2000$ was invested into the $ 6\%$ paying account, and
${{\$}} 5000$ was invested into the $ 8\%$ paying account.
Work Step by Step
Let $ x $ = amount invested into the $ 6\%$ paying account.
Interest earned from the $ 6\%$ paying account = $0.06x $
The rest of the investment, $(7000-x)$ earns $ 8\%$, which equals $\qquad $
$0.08(7000-x)$
The sum of these amounts earned is ${{\$}} 520:$
$0.06x+0.08(7000-x)=520$
$0.06x+560-0.08x=520$
$-0.02x=520-560$
$-0.02x=-40 \qquad $ ... multiply with $-50$
$ x=2000$
So, ${{\$}} 2000$ was invested into the $ 6\%$ paying account, and
${{\$}} 5000$ was invested into the $ 8\%$ paying account.
