Formulate a system of equations for the situation below and solve.
A) Michael Perez deposited a total of $3000 with two savings institutions. Bank A pays interest at the rate of 5%/year, whereas Bank B pays interest at the rate of 7%/year. If Michael earned a total of $194 in interest during a single year, how much did he deposit in each institution?
Bank A ___ $
Bank B ___ $
B) Kelly Fisher invested a total of $20,000 invested in two municipal bonds that have yields of 8% (bond A) and 9% (bond B) interest per year, respectively. If the interest Kelly receives from the bonds in a year is $1720, how much did she invest in each bond?
bond A ____ $
bond B ____ $