Question

Find the area of an isosceles triangle whose perimeter is 11cm and base is 5 cm

Answer 1

27.5 as 1/2*55[11*5] = 55/2 = 27.5

Answer 2

given base of isoceles triangle (b)= 5cm

let a , a be the two equal sides of isoceles triangle .

given ,perimeter = 11 cm

a + a + b = 11 cm

2a + b = 11 cm

2a + 5 =11

2a = 6

a = 3 cm

area of isoceles triangle

= b/4 √(4a^2 - b^2 )

=5 / 4 √{4(3)^2 - (5)^2 }

=5 /4 √(36 - 25 )

=5 /4 √11 = 5 × 3.31 / 4

= 16.58 /4 = 4.14 cm^2

therefore, area of isoceles triangle

= 4.14 cm^2
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Your Answer : area =4.14 cm^2
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