Juanita has 38000 to invest in two accounts that pay simple

Juanita has $38,000 to invest in two accounts that pay simple interest on an annual basis. One account pays 4% in simple interest, and the other pays 2% simp interest. How much would she have to invest in each account to earn a total interest of $980 after one year? She would have to invest at 4% simple interest and at 2% simple interest. (Simplify your answers

Solution

(1) Let x = the amount invested at 4% interest and

y= the amount invested at 2% interest

Then x + y = 38000

So, y = 38000 - x ... (1)

Also, 0.04x + 0.02y = 980 ... (2)

Substituting the value of y from (1) in (2),

0.04x + 0.02 (38000 - x) = 980

0.04x + 760 - 0.02x = 980

0.02x + 760 = 980

0.02x = 220

x= 11000

Substituing this in (1),

y = 38000 - 11000 = 27000

So the amount invested at 4% = $11,000 and

the amount inested at 2% = $27, 000

(2) The x-intercept is where the line cuts the x-axis and it is 3.

The y-intercept is where the line cuts the y-axis and it is 5.