Traditionally people start smoking at 19, with a standard deviation of 2.1. a survey of 40 smokers in 2015 was conducted and produced a sample mean is 18.1. i made all these numbers up.

answer: hey there,

the answer you are looking for is a..

hope this you!

step-by-step explanation:

your mom

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