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Junior high school triangles are similar to triangles ABC and def. If AB is equal to ab + de and AC is equal to AC + DF, is that ab Triangle similarity in junior high school Triangle ABC and triangle def, if AB than AB + de equals AC than AC + DF, is ab than de equal to AC than DF? Why? If the angle BAC equals the angle EDF, are the two triangles similar? Why?
(1) Equal
AB/(AB+DE)=AC/(AC+DF)
Take the reciprocal
(AB+DE)/AB=(AC+DF)/AC
1+DE/AB=1+DF/AC
DE/AB=DF/AC
Then take the reciprocal
AB/DE=AC/DF
(2) Similar
The two sides are proportional and the angles are equal
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