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प्रश्न
AM and DN are the altitudes of two similar triangles ABC and DEF. Prove that: AM : DN = AB : DE.
उत्तर
Since ΔABC ∼ ΔDEF
∠B = ∠E
∠AMB = ∠DNE ...(Both are right angles)
Therefore, ΔANB ∼ ΔDNE
∴ `"AM"/"DN" = "AB"/"DE"`
⇒ AM : DN = AB:DE.
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