You split $2200 between two savings accounts. account a pays an annual interest rate of 5% and account b pays an annual interest rate of 3%. after one year, you have earned a total of $78.50 in interest. how much money did you invest in each account?

Step-by-step explanation:

Let x be the amount at 5%

Then 2200 - x is the amount at 3%

The total interest is:

Find the amount at 3%:

the system of inequalities is

step-by-step explanation:

step 1

find the equation of the dashed line

we have the points

(0,0) and (3,1)

the line passes through the origin, so, is a direct variation

find the slope

the equation of the dashed line is

the solution of the inequality a s the shaded area above the dashed line

therefore

the equation of the inequality a is

step 2

find the equation of the solid line

we have the points

(4,0) and (0,4)

find the slope

the equation of the solid line is

the solution of the inequality b s the shaded area below the solid line

therefore

the equation of the inequality b is

step 3

the system of inequalities is