Jolene invests her savings in two bank accounts

Question

Jolene invests her savings in two bank accounts, one paying 6 percent and the other paying 9 percent simple interest per year. She puts twice as much in the lower-yielding account because it is less risky. Her annual interest is 3276 dollars. How much did she invest at each rate?

Answer 1

.06x+ .09y =3276

6x+9y=327600

x=2y

21y=327600

y=327600/21= 109200/7=15600

y=$15,600 at 9%

x= $31,200 at 6%

Answer 2

0.06(2a) + 0.09a = 3276

Can you solve for a and answer?