(a 2 b 2 + 2/3 b 2 ) + (--1/6 b 2 + 2/3a 2 b 2 ) + (-- 5/6 a 2 b 2 + 2/3 b 2 )

Last year, laura had $30,000 to invest. she invested some of it in an account that paid 7% simple interest per year, and she invested the rest in an account that paid 8% simple interest per year. after one year, she received a total of $2230 in interest. how much did she invest in each account?