A homeowner wants to determine how much paint is needed to paint the walls of his living room. Choose the two variables the homeowner should most consider when deciding how much paint is necessary.
A.
the cost of one gallon of paint
B. the number of rooms in the house
c. the number of walls in the living room
D. the area of the walls in the living room
E. the area that one gallon of paint will cover

this doesn't make sense lol

i think it would be 42cm

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