How can $12,600 be split between two investments, one paying 6% annually and one paying 8% annually so that the interest from the two accounts equals $864

If x is at 6%, then the rest (12600-x) is at 8%. So, add up the interest:

.06x + .08(12600-x) = 864.00

To solve this problem, we can set up a system of linear equations. Let's denote the amount of money invested at 6% by x and the amount invested at 8% by y.

The first equation represents the total amount invested:

x + y = $12,600

The second equation represents the total interest earned:

0.06x + 0.08y = $864

To solve this system of equations, we can use substitution or elimination method. Let's use the elimination method:

Multiply the first equation by 0.06:

0.06(x + y) = 0.06($12,600)
0.06x + 0.06y = $756

Now subtract this equation from the second equation:

(0.06x + 0.08y) - (0.06x + 0.06y) = $864 - $756
0.02y = $108

Divide both sides of the equation by 0.02:

y = $108 / 0.02
y = $5,400

Now substitute the value of y back into the first equation and solve for x:

x + $5,400 = $12,600
x = $12,600 - $5,400
x = $7,200

Therefore, $7,200 should be invested at 6% and $5,400 should be invested at 8% in order to earn a total of $864 in interest.