PSLEIn the figure, CDEF is a parallelogram. CAF and AEB are straight lines. ∠BEF = 151°, ∠CFE = 42° and ∠CEA = 17°.
- Find ∠DEB.
- Find ∠DCE.
(a)
∠DEF
= 180° - 42°
= 138° (Interior angles)
∠DEB
= 360° - 151° - 138°
= 71° (Angles at a point)
(b)
∠FEA
= 180° - 151°
= 29°(Angles on a straight line)
∠DCE
= ∠CEF
= 29° + 17°
= 46° (Alternate angles)
Answer(s): (a) 71°; (b) 46°