Mr. Smith invest a certain amount of money at 8% interest and twice as much at 5% his annual income from the two Investments is $720 how much does he have invested at 5% in dollars

he invested $8000 at 5%

Step-by-step explanation:

Let x represent the amount which he invested in the account paying 8% interest.

Let y represent the amount which he invested in the account paying 5% interest.

Mr. Smith invest a certain amount of money at 8% interest and twice as much at 5% . This means that

xmy = 2x

The formula for determining simple interest is expressed as

I = PRT/100

Considering the account paying 8% interest,

P = $x

T = 1 year

R = 8℅

I = (x × 8 × 1)/100 = 0.08x

Considering the account paying 5% interest,

P = $y

T = 1 year

R = 5℅

I = (y × 6 × 1)/100 = 0.05y

His annual income from the two Investments is $720 it means that

0.08x + 0.05y = 720 - - - - - - - - - -1

Substituting y = 2x into equation 1, it becomes

0.08x + 0.05 × 2x = 720

0.08x + 0.1x = 720

0.18x = 720

x = 720/0.18

x = 4000

y = 2x = 2 × 4000

y = $8000

what is the original number? you forgot to add it.

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.