Alegbra Mixture Problem?

Question

Editon Longwell invested $33,600, part at 5% interest and the remainder at 8% interest. If he earned twice at much from his 5% investment at his 8% investment, how much did he invest at each rate?

Answer 1

(.05)x = 2 (.08)(33,600-x)

.05x = 5376 - .16x

.21x = 5376
x = 25600

so $25600 is invested at 5% and $8000 at 8%

Answer 2

OK.

X= amt invested at 5%
33,600-X = amt invested at 8%

So:

X * 0.05 = 2* (33,600 - X) * 0.08

0.05 X = 0.16( 33,600 - X) = 5376 - 0.16X

0.05X + 0.16X = -5376

0.21X = 5376

X=$25,600 (amt invested at 5%)

$33,600 - X= $8,000 (amt invested at 8%)

Done.