28 + 6 = 34 and 34 - 3 = 31!!!!!!!
Set up 2 different equations for each day and then solve using substitution or elimination
<u>Please</u><u> </u><u>put</u><u> </u><u>a</u><u> </u><u>picture</u><u> </u><u>next</u><u> </u><u>time</u><u> </u><u>:</u><u>)</u>
DI/dx=-850x+45500
d2l/d2x=-850 so when dl/dx=0 it is an absolute maximum for l(x)...
dl/dx=0 only when:
850x=45500
x=53.53
x=54 years of age (rounded)
I=prt. I=600(.07)(2). I=42(2). I=84. Juanita will pay $84 interest :)