Answer:
x = 7.5
Step-by-step explanation:
We first labelled the diagram we get
DC = 8
AD = 10
CE = 6
BE = x
∴ AC =AD + DC = 18
∴ BC = BE + ED = x + 6
To Find :
BE = x =?
Solution:
Let DE || AC
In Δ ABC and Δ DEC
∠A ≅ ∠D …………..{corresponding angles ∵ DE || AB }
∠B ≅ ∠E ..............{corresponding angles ∵ DE || AB }
∠C ≅ ∠C ……….....{Reflexive Property}
Δ ABC ~ Δ DEC ….{Angle-Angle-Angle Similarity test}
If two triangles are similar then their sites are in proportion.
[tex]\frac{AB}{DE} =\frac{BC}{EC} =\frac{AC}{CD}\ \textrm{corresponding sides of similar triangles are in proportion}\\[/tex]
On substituting the given values we get
∴ [tex]\frac{8}{18} = \frac{6}{6+x} \\\\8(6+x) = 6\times 18\\\\\textrm{using distributive property we get}\\48+8x=108\\8x=108-48\\x=\frac{60}{8}\\ \\x=7.5\\\\\therefore x =7.5[/tex]
