You know that Mike gets paid $45 for 3 hours and $105 for 7 hours. How much money will Mike make if he babysits for 8.5 hours?

$127.50

Step-by-step explanation:

$45/3 = $15 per hour

$15 x 8.5 = $127.50

127.50 dollars

Step-by-step explanation:

He makes $15/an hour because $45/3 = $15. 15 x 8.5 = $127.50.

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