Final answer:
To find the amount borrowed at 10%, we can solve a system of equations based on the given information. The amount borrowed at 10% is $15,000.
Step-by-step explanation:
To solve this problem, we need to set up a system of equations based on the given information.
Let's assume that the amount borrowed at 10% is x, the amount borrowed at 12% is y, and the amount borrowed at 14% is z.
The first equation we can form is:
x + y + z = $45,000 (the total amount borrowed).
The second equation is:
x + y = 2z (the total amount borrowed at 10% and 12% is twice the amount borrowed at 14%).
The third equation is based on the annual interest of
$5,420: 0.10x + 0.12y + 0.14z = $5,420.
Using Gaussian elimination or Gauss-Jordan elimination, we can solve this system of equations to find the values of x, y, and z.
After solving, we find that the amount borrowed at 10% is $15,000.