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ABC is a triangle, right-angled at B. M is a point on BC. Prove that: AM2 + BC2 = AC2 + BM2 - Mathematics

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प्रश्न

ABC is a triangle, right-angled at B. M is a point on BC.

Prove that: AM2 + BC2 = AC2 + BM2

योग
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उत्तर

The pictorial form of the given problem is as follows:

Pythagoras theorem states that in a right-angled triangle, the square on the hypotenuse is equal to the sum of the squares on the remaining two sides.

First, we consider the ΔABM and applying Pythagoras theorem we get,

AM2 = AB2 + BM2 

AB2 = AM2 - BM2               ...(i)

Now, we consider the ΔABC and applying Pythagoras theorem we get,

AC2 = AB2 + BC2 

AB2 = AC2 - BC2                ...(ii)

From (i) and (ii) we get,

AM2 - BM2 = AC2 - BC2 

AM2 + BC= AC2 + BM2  

Hence, Proved.

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 13: Pythagoras Theorem [Proof and Simple Applications with Converse] - Exercise 13 (B) [पृष्ठ १६३]

APPEARS IN

सेलिना Concise Mathematics [English] Class 9 ICSE
अध्याय 13 Pythagoras Theorem [Proof and Simple Applications with Converse]
Exercise 13 (B) | Q 3 | पृष्ठ १६३

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