Question

2 points
Question 8. find the area of
isosceles triangle whose each
of the equal side is 15cm and
third side is 10cm.उस समद्विबाहु
त्रिभुज का क्षेत्रफल ज्ञात कीजिए जिसकी
प्रत्येक समान भुजा 15cm हो और
तीसरी भुजा 10cm हो।
17​

Answer 1

$\bf{\huge{\boxed{\star{\bf{AnswEr\:-:}}}}}$

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$\sf{Area\:of\:Triangle\:= 70.71cm^{2}}$

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$\large{\sf{Formulas\: used\: in\:question.......}}$

$\Rightarrow{\sf{Area \:of\:triangle\:-:}}$

$\sf{A\:= \sqrt{s\: (s-a)\:(s-b)\:(s-c)}}$

$\sf{Here\:,}\\\\{\sf{A = \: Area}}\\\\{\sf{s=\:Semi\:Perimeter}}\\\\{\sf{A,\:B\:and\:C=\: Length\:of\:Three\: sides\:of\:Triangle}}$

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$\large{\sf{Given\:-:}}\\\\{\sf{\star{Length\:of\:two\:equal\:sides\:of\:triangle\:=15cm}}}$

$\sf{\star{Length\:of\:third\:side\:of\:triangle\:=10cm}}$

$\large{\sf{To\:Find\:,}}$

$\sf{\star{Area\:of\:Triangle}}$

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$\large{\sf{Solution\:,}}\\{\sf{Now,}}$

$\sf{\star{Semi\:Perimeter-:\frac{a+b+c}{2}}}$

$\sf{Here,}\\{\sf{A = length\:of\:first\:side\:of\:triangle\:= 15cm}}\\{\sf{B=length\:of\:second\:side\:of\:triangle\:=\:15cm}}\\{\sf{C=length\:of\:first\:side\:of\:triangle\:=\:10cm}}$

$\sf{\star{Semi\:Perimeter-:\frac{15+15+10}{2}}}$

$\sf{\star{Semi\:Perimeter-:\frac{40}{2}}}$

$\sf{\star{Semi\:Perimeter-:20cm}}$

$\Rightarrow{\sf{Area \:of\:triangle\:-:}}$

$\sf{A\:= \sqrt{s\: (s-a)\:(s-b)\:(s-c)}}$

$\sf{Here\:,}\\\\{\sf{A = \: Area=\:??}}\\\\{\sf{s=\:Semi\:Perimeter-:\:20cm}}$

$\sf{A = \: 15cm}\\{\sf{B=\:15cm}}\\{\sf{C=\:10cm}}\\\\{\sf{A\:= \sqrt{20\: (20-15)\:(20-15)\:(20-10)}}}$

$\sf{A\:= \sqrt{20\times5\times5\times10}}$

$\sf{A\:= \sqrt{5000}}$

$\sf{A\:= 70.71cm^{2}}$

$\large{\sf{Hence\:,}}\\\\{\sf{Area\:of\:Triangle\:= 70.71cm^{2}}}$

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