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If the sides of a triangle are 3 cm, 4 cm and 5 cm, then the area is

#### Options

3 cm

^{2}6 cm

^{2}9 cm

^{2}12 cm

^{2}

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#### Solution

**6 cm ^{2}**

**Explanation;**

Hint:

a = 3 cm, b = 4 cm, c = 5 cm

s = `("a" + "b" + "c")/2`

= `(3 + 4 + 5)/2`

= 6 cm

Area of the triangle = `sqrt("s"("s" - "a")("s" - "b")("s" - "c"))`

= `sqrt(6 xx 3 xx 2 xx 1)`

= `sqrt(36)`

= 6 cm^{2}

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