Question

The combined yearly interest for x dollars invested at 12​% and 45,000−x dollars invested at 8​% is​ ________.

Answer 1

.12x + .08(45000-x)
.12x + 3600 - .08x
.12x - .08x + 3600
.04x + 3600

combined yearly interest = .04x + 3600

Answer 2

`3600+0.04x`

Explanation:

We are asked to find the combined yearly interest for both amounts.

The interest for x dollars invested at 12​% would be 12% of x.

`12\%\text{ of }x=(12)/(100)x=0.12x`

The interest for
`45,000-x` dollars at 8% would be 8% of
`45,000-x`.

`(8)/(100)(45,000-x)`

`0.08(45,000-x)`

`3600-0.08x`

Combined interest:
`3600-0.08x+0.12x`

`3600+0.04x`

Therefore, the combined tax would be
`3600+0.04x`.