Last year, juan had $30,000 to invest. he invested some of it in an account that paid 7% simple interest per year, and he invested the rest in an account that paid 9% simple interest per year. after one year, he received a total of $2320 in interest. how much did he invest in each account?

Let x be the amount invested at 7%, leaving 30000-x to be invested at 9%.

The equation is

2320 = 0.07 x + 0.09 (30000 - x)

2320 = -0.02 x + .09(30000)

0.02 x = .09(30000) - 2320

x = ( .09(30000) - 2320) / .02

x = 19000

$19000 at 7%, $11000 at 9%

Check:

19000(.07)+11000(.09) = 2320, good

(- 1, 0 )

step-by-step explanation:

an x- intercept is where the function crosses the x- axis.

to find the x- intercept/s look for the value of x when f(x) = 0

from the given table there are 3 values of x where f(x) = 0

when x = - 1, x = 2, x = 3

the one that is listed is (- 1, 0 )