Answer:
Let x represent the amount of $ in the 4% account and y in the 2% account.
Then x + y = $4000 (total savings).
Interest at 4% would be x*0.04*1 = 0.04x, and
Interest at 2% would be y*0.02*1 = 0.02y.
Then 0.04x + 0.02y = $140 interest, total.
We must solve this system of linear equations.
Mult. 0.04x + 0.02y = $140 by 100 to remove the fractions:
4x + 2y = $14000 We already know that x + y = $4000, so y = $4000-x.
Then 4x + 2y = $14000 becomes 4x + 2($4000-X) = $56000.
Simplifying, 4x + $8000 - 2x = 14000.
2x = $6000
x = $3000 at 4%
y = $1000 at 2%
i hope it helps :)
Explanation: