The lengths of the sides of a triangle are 5 m, 5 m and 8 m. What is the area of the triangle? |
$12 m^2$ $15 m^2$ $18 m^2$ $20 m^2$ |
$12 m^2$ |
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 |