2. investments salvador's investment of
$2,200 in the stock market earned $528
in two years. find the simple interest
rate for this investment.

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

hi,

the area of abcd is 245.

3*24=230

4*94=1039

2*12=24

add all of them up, you get 2450