A woman invested 4 times much at 4% as she did at 9%. The total amount of interest she earns in 1 year from both accounts is $500. How much did she invest at each rate?

$2,000 at 9%

$8,000 at 4%

Step-by-step explanation:

(4x * .04) + (x * .09) = 500

.16x + .09x

.25x = 500

x = $2,000 at 9%

4x = $8,000 at 4%

2000 at 9%

8000 at 4%

Step-by-step explanation:

Let the principle at 9% = x

The principle at 4% = 4*x

Together they give 500 dollars.

9% = .09

4% = ,04

Both are invested for 1 year

0.09 * 1 * x + 0.04 * 1 * 4x = 500

0.09x + 0.16x = 500

0.25x = 500

x = 500 / 0.25

x = 2000

She invested 2000 at 9%

She invested 4 * 2000 at 4%