Answer:
98.1km²
Explanation:
The name of the Triangle in this question is: WXV
In the question, we have:
Angle W = ? Unknown
Angle X = 119°
Angle V = 34°
Side w =?
Side x = 26km
Side v = ?
Step 1
We have to find the missing third angle = Angle W
Sum of angles in a triangle = 180°
= Angle W = 180° - (119 + 34)°
= 180° - 153°
Angle W = 27°
Step 2
Find the sides w and v using the sine rule
Sine rule =
a/ sin A = b/ Sin B
Hence for triangle WXV
w/ sin W = x/ sin X = v/ sin V
We have the following values
Angle W = 27°
Angle X = 119°
Angle V = 34°
We are given side x = 26km
a) Finding side w
w/ sin W= x/ sin X
w/sin 27 = 26/sin 119
Cross Multiply
sin 27 × 26 = w × sin 119
w = sin 27 × 26/sin 119
w = 13.49587km
w = 13.5km
b) Finding side v
x / sin X= v/ sin V
26/ sin 119 = v/sin 34
Cross Multiply
sin 119 × v = 26 × sin 34
v = sin 34 × 26/sin 119
v = 16.62324km
v = 16.62km
Step 3
Detemine the area of triangle WXV
We make use heron formula
= √s(s - w) (s - x) (s - v)
Where s = w + x + v/ 2
s = (13.5 + 26 + 16.62)/2
s = 56.12/2
s = 28.06
Area of the triangle = √28.06× (28.06 - 13.5) × (28.06 - 26 ) × (28.06 - 16.62)
Area of the triangle = √9628.137559
Area of the triangle = 98.123073530337km²
Approximately to the nearest tenth =98.1km²