Question

Find the area of the triangle.area triangle 1A. 14.1 km²B. 12.8 km²C. 15.2 km²D. 14.7 km²

Answer 1

Given:

a = 7 km

b = 6 km

c = 5 km

To find the Area of the triangle, we use Heron's formula, as follows:

$A=\sqrt{s(s-a)(s-b)(s-c)}$

where s:

$Semi\text{ }Perimeter\text{ }(s)=\frac{a+b+c}{2}=\frac{7+6+5}{2}=9km$

hence:

$A=\sqrt{9\times(9-7)\times(9-6)\times(9-5)}=14.7km^2$

ANSWER

D. 14.7 km²