An investment of $8500 increases in value by 4.5% every year. How long until the investment reaches about $17,323. Round to the nearest whole year

17 years

Step-by-step explanation:

We can use a known formula (n being the number of years)

n = log(17323/8500) / log (1+ 0.045) = 16.17

triangle and cube

step-by-step explanation:

we have three similar triangles, because each has a right angle and shares an angle.   let's write the angles in order: opposite to short leg, long leg, hypotenuse.

cab similar to bad similar to cbd

or as ratios,

ca: ab: cb = ba: ad: bd = cb: bd: cd

we also know

ac = ad + cd

(ad+cd): ab: cb = ba: ad: bd = cb: bd: cd

(ad+cd)/cb=cb/cd

we have cb=6, ad=5 and seek x=cd.

we reject the negative root and conclude x=4

answer: 4