Question

1. Ava invests a total of $1,000 in three accounts, one paying 5% interest, another paying 5% interest, and the third paying 8% interest. The annual interest earned on the three investments last year was $570. The amount invested at 9% was twice the amount invested at 5%. Determine the coefficient Matrix and find the rank of the phenomena

Answer 1

Answer:

We have seen how to write a system of equations with an augmented matrix, and then how to use row operations and back-substitution to obtain row-echelon form. Now, we will take row-echelon form a step farther to solve a 3 by 3 system of linear equations. The general idea is to eliminate all but one variable using row operations and then back-substitute to solve for the other variables.