Solve the problem by using a system of equations.
1. A motel rents double rooms at $31 per day and single rooms at $24 per day. If 25 rooms were rented one day for a total of $698, how many rooms of each kind were rented?
______ single rooms
______ double rooms
2. Sam invested $1850, part of it at 6% and the rest at 8% yearly interest. The yearly income on the 8% investment was $38 more than twice the income from the 6% investment. How much did he invest at each rate?
Investment at 6% $_____
Investment at 8% $_____
BTW the given equations define lines on a graph, so you can also find the answer by graphing, like this:
www.wolframalpha.com/input/?ab=c&i=solve+x+%2B+y+%3D+25,+31x+%2B+24y+%3D+698