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We have `r_(1) = r_(2) + r_(3) + r` <br> or `r_(1) - r = r_(2) + r_(3)` <br> `rArr (Delta)/(s -a) -(Delta)/(s) = (Delta)/(s -b) + (Delta)/(s -c)` <br> or `(Delta a)/(s(s -a)) = (Delta (2s -b -c))/((s-b) (s-c)) = (Delta a)/((s-b) (s-c))` <br> or `s(s -a) = (s -b) (s -c)` <br> or `s^(2) - sa = s^(2) - (b + c) s + bc` <br> or `2s (b + c-a) = 2bc` <br> or `(a + b + c) (b + c-a) = 2bc` <br> or `(b + c)^(2) - a^(2) = 2bc` <br> or `b^(2) + c^(2) = a^(2)` <br> Hence, the triangle is right angledTranscript

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00:00 - 00:59 | triangle are 1 is equal to 2 + 3 + are need to prove that a triangle is right angled it is given to us that our 1 minus is equal to 2 + 8 C value of iron is equal to tell by x minus value addition to tell by value of 8 2012 by x minus b vol 53 is equal to tell by x minus C what will do is taking action on both sides will get Dell a divided by X into x minus A is equal to that of a minus b + c / S minus b into x minus |

01:00 - 01:59 | which can also be written as dead by a minus is equal to us we know that s is equal to a + b + c y to we can put the value we can put the value of B + C is equal to minus A putting this in this occasion we will get Delta b b minus b minus C delta delta both sides will get into x minus A is equal to x minus b into x minus 6 question for the really get a square minus is equal to x square - |

02:00 - 02:59 | a + b + BC which means that a b + c minus A is equal to price of BC this will get this equation is for this means that as we know that s is equal to a + b + Y2 and it is only number + c minus 3 is equal to 2 BC cancelling to Bittu will get b + c ka whole square minus A square is equal to BC opening his capture system will get please paper 80 square + 2 b c minus A square is equal to 2 BC which gives b square + c square is equal to a square is allowed to BC |

03:00 - 03:59 | which is the condition of the right angle triangle therefore the triangle is right angled with this condition is only confirmed by right angle triangle |

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