PSLE In the figure, RSWX is a parallelogram and TUVW is a rhombus. XWV is a straight line. ∠SRX = 57°, ∠WST = 25° and ∠UTV = 32°.
- Find ∠SWT.
- Find ∠STU.
(a)
∠SWX
= ∠SRX
= 57° (Parallelogram)
∠UVT
= ∠UTV
= 32° (Isosceles triangle)
∠TUV
= 180° - 32° - 32°
= 105° (Angles sum of triangle)
∠TWV
= ∠TUV
= 105° (Rhombus)
∠SWT
= 180° - 57° - 105°
= 18° (Angles on a straight line)
(b)
∠STW
= 180° - 25° - 18°
= 137° (Angles sum of triangle)
∠VTW
= ∠UTV
= 32° (Rhombus)
∠STU
= 360° - 137° - 32° - 32°
= 159° (Angles at a point)
Answer(s): (a) 18°; (b) 159°