You need exactly 47 bottles of water. you don’t want to buy more than you need, but you want the least expensive way. list the best way to buy exactly 47 bottles of water. single bottle: $1.25 6-pack: $7.20 12-pack: $13.80 case (24): $26.40

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

x=-7

step-by-step explanation:

x+3=-10

-10+3=-7

x=-7