Answer:
$9000 was invested into the first account for 4% interest.
$16,000 was invested into the second account for 11% interest.
Step-by-step explanation:
Let "a" be the money invested in the first account , 4%
let "b" be the money invested in the second account , 11%
The equation for the total interest is:
0.04a + 0.11b = 2120
I converted 4% and 11% into decimal form by dividing by 100.
The equation for total investment is:
a + b = 25,000
Solve the system between these two equations:
Rearrange a + b = 25000 to isolate one of the variables. I will isolate for "b".
a + b = 25000
b = 25000 - a
Substitute b = 25000 - a into the other equation
0.04a + 0.11b = 2120
0.04a + 2750 - 0.11a = 2120 Use distributive property over brackets
2750 - 0.07a = 2120 Combine the like terms with variable "a"
-0.07a = -630 Subtract 2750 from both sides
a = -630/-0.07 Divide both sides by -0.07
a = 9000
Substitute a = 9000 into an equation to find "b" . Choose a simpler equation
b = 25000 - a
b = 25000 - 9000
b = 16000
Therefore $9000 was invested into the account paying 4% interest. $16,000 was invested into the account paying 11% interest.