Question

Find the area (in $c{m}^2$) of a triangle, two sides of which are 8 cm and 12 cm and the perimeter is 38 cm .

• A. 16
• B. 16
• C. √1463
• D. 24√3

Answer 1

The correct option is C

√1463

Third side = perimeter - (sum of other two sides) = 38 - 20 = 18 cm
Semi perimeter of a triangle = $\frac{perimeter}{2}=\frac{38}{2}=19cm$
Area of a triangle = $\sqrt{s(s-a)(s-b)(s-c)}$
$=\sqrt{19(19-12)(19-8)(19-18)}$
$=\sqrt{1463}$ $c{m}^2$