Question 908710
We don't know the total invested.
We know the difference in the two accounts.
We know that the interest for the two accounts is $1280
0.12*x+0.1*y=1280
We know that the account at 12% has $3000 more.
x=3000+y
We substitute for x
0.12*(3000+y)+0.1*y=1280
We multiply out
360+0.12y+0.1*y=1280
We combine like terms.
0.22*y=920
Isolate y
y=$4181.82 at 10%
x=3000+y
Calculate x
x=$7181.82 at 12%
Now,we know the total invested is: 11363.64
Total invested $7181.82+$4181.82=$11363.64
We check
0.12*7181.82+0.1*4181.82=1280
861.82+418.18=1280
1280.0=1280
Since this statement is TRUE and neither x nor y is negative all is well.