Similar triangles concept issue

GRE Quant Problem Solving
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in the triangle ARB how come base is AR and not BR? could anyone help

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They are trying to use the property of similar triangles.

For that reason, we first need to represent the 2 triangles such that they are similar (meaning, rotate the triangles in such a way, that the corresponding angles in both the trriangles match)

For that, we need to rotate the left triangle, to match the angle ‘x’ in both the triangles.
So the base changes.

1 Like
3

thank you for sparing some time and helping but like after rotating how would we match x? and how to know when base changes in which all case?

thank you!