Answer:
3
Explanation:
Because the triangles are similar
6/4 = (?+6)/(2+4)
6/4 = (?+6)/6
Cross multiply
36 = 4?+24
4?=12
?=3
? = 3
given a line parallel to a side of the triangle and intersecting the other 2 sides, then it divides those sides proportionally , that is
= ( cross- multiply )
4? = 12 ( divide both sides by 4 )
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( cross- multiply )