Answer:
x = 9/4
Step-by-step explanation:
Locate point G on segment DE so that DG = 1 and GE = 4. CG is parallel to AD, so ΔCGE ~ ΔABC. Corresponding sides are proportional.
AB/BC = CG/GE
x/1 = 9/4
x = 9/4
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Additional comment
Using the given triangles, you can write the proportion statement as ...
(9+x)/x = 5/1
We judge this to take more steps to solve, so we prefer the method shown above.
