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Question
If the sides of a triangle are 3 cm, 4 cm and 5 cm, then the area is
Options
3 cm2
6 cm2
9 cm2
12 cm2
Solution
6 cm2
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 cm2
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