The lengths of the sides of a triangle are 5 m, 5 m and 8 m. What is the area of the triangle?
Answer & explanation
Correct answer: option 1
The correct answer is Option 1: $12 m^2$
Step 1: Calculate the semi-perimeter (s)
s= (5+5+8)/2 =9m
Step 2: Use Heron's formula for area (A): √s(s-a)(s-b)(s-c)
A = √9 (9-5)(9-5)(9-8)
=√9*4*4
=√144 = $12 m^2$
Alternatively, We can find the area of the triangle by finding the height of the triangle.
Using the Pythagorean theorem: $hypotenuse^2$ = $base^2$ + $height^2$
$5^2$ = $4^2$ + $height^2$
$height^2$ =25 - 16 = 9
Height = 3 m
Area = 1/2 x base x height
= 1/2 x 8 x 3
= 12 m