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(4x4 = 10)33ra) The perimeter of an isosceles triangle is 32 cm. The ratio of the equal side to itsbase is 3:2. Find the area of the triangle. |
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Answer» [32\sqrt{2}cm^{2} ] Given\; perimeter\; of\; isosceles\; triangle = 32 cm We\; have\; ratio\; of\; equal\; side\; and\; base = 3 : 2 Thus,\; let\; the \; sides\; of\; triangle\; be\; AB = AC = 3x\; and\; BC = 2x \therefore Perimeter \; of\; a\; triangle = 32 cm 3x + 3x + 2x = 32 8x = 32 x=\frac{32}{8} x = 4 cm So, AC = AB = 3 \times 4 cm\; and\; BC = 2 \times 4 cm AC = AB = 12 cm\; and \; BC = 8 cm
Now, a = 8\; cm, b = 12\; cm, c = 12 \; cm Using Heron’s formula S= \frac{a+b+c}{2}=\frac{8+12+12}{2}=\frac{32}{2}=16cm \therefore\; AREA \; of\; isosceles\; triangle\; \Delta ABC =\sqrt{S\left ( S-a \right )\left ( S-b \right )\left ( S-c \right )} =\sqrt{16\left ( 16-8 \right )\left ( 16-12 \right )\left ( 16-12 \right )} = \sqrt{16\times 8\times 4\times 4} = \sqrt{4\times 4\times 4\times 2\times 4\times 4} =4\times 4 \sqrt{ 2\times 2\times 2}=4\times 4\times 2\sqrt{2}=32\sqrt{2}\; cm^{2} HENCE,\; the\; area\; of\; isosceles \; triangle\; is\; 32\sqrt{2}\; cm^{2}
Step-by-step explanation: |
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