rate investment system of equations

Question

A man invests his savings in two accounts, one paying 6% and the other paying 10% simple interest per year. He puts twice as much in the lower-yielding account because it is less risky. His annual interest is $10296 dollars. How much did he invest at each rate?

Amount invested at 6% equals = ???

Amount invested at 10% equals = ???

Answer 1

.06(2x) + .10(x) = 10,296

.22x = 10296

x = 10296/.22 = 46800

$46,800 invested at 10%

$93,600 invested at 6%

total invested is $140,400 earning $10,296

an average rate of return of 10296/140400 = 0.07333... = 7 1/3 %

10-7 1/3 = 2 2/3

7 1/3 -6 = 1 1/3

2 2/3 is twice 1 1/3, same as twice as much invested at the rate 6% which is closer to the average rate of return than 10%

Answer 2

i = p * r * t

0.06x + 0.10(2x) = 10296

Cam you solve for x and answer?