Question 906711
Total amount of money invested: $30000
x+y=30000,
Total yearly interest for the two accounts is: $2400
0.12*x+0.04*y=2400
x=30000-y
Substitute for x
0.12*(30000-y)+0.04*y=2400
Multiply out
3600-0.12y+0.04*y=2400
Combine like terms.
-0.08*y=-1200
Isolate y
y=$15000.00 at 4%
x=30000-y
Calculate x
x=$15000.00 at 12%
Check
0.12*15000+0.04*15000=2400
1800+600=2400
2400=2400
If this statement is TRUE and neither x nor y  is negative then all is well