Juanita constructed a number line to test her brother’s understanding of opposites. She tested him on all points that were labeled with letters. Her brother had trouble representing the opposite of point A.

Which represents the opposite of Point A?
-(-10)
-(-5)
0
-(10)

-(10)

Step-by-step explanation:

Each division is 5 units.

A is 2 divisions towards left of 0

-(2×5)

-(10)

(c, 0) i might be wrong so don't put full faith on my answer

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