9=6+3c
Can you help me?

3c=9-6

3c=3

3c/3=3/3

c=1

c=1

Step-by-step explanation:

subtract 6 on both sides: 3=3c

divide 3 on both sides: 3/3=3c/3

1 is equal to c

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