PSLE In the figure, RSWX is a parallelogram and TUVW is a rhombus. XWV is a straight line. ∠SRX = 57°, ∠WST = 28° and ∠UTV = 35°.
- Find ∠SWT.
- Find ∠STU.
(a)
∠SWX
= ∠SRX
= 57° (Parallelogram)
∠UVT
= ∠UTV
= 35° (Isosceles triangle)
∠TUV
= 180° - 35° - 35°
= 102° (Angles sum of triangle)
∠TWV
= ∠TUV
= 102° (Rhombus)
∠SWT
= 180° - 57° - 102°
= 21° (Angles on a straight line)
(b)
∠STW
= 180° - 28° - 21°
= 131° (Angles sum of triangle)
∠VTW
= ∠UTV
= 35° (Rhombus)
∠STU
= 360° - 131° - 35° - 35°
= 159° (Angles at a point)
Answer(s): (a) 21°; (b) 159°