Question 18
Triangles and QuadrilateralsCalculate the value of x in the diagram below
- A.18°
- B.30°
- C.40°
- D.60°
- E.It cannot be determined.
Show the answer and explanation
Answer: A (18°)
Explanation
Each 3x angle is vertically opposite an angle of the triangle, so the triangle's angles are 3x, 3x and 4x. Then 10x = 180°, so x = 18°.