PSLE HJKL and KNQM are identical parallelograms. PKJ and MLK are identical right-angled triangles.
- Find ∠r.
- Find ∠s.
- Select the words that describe JPN in the statement:
JPN (is/is not) a straight line because the sum of angles JPK and KPN (is/is not) 180° Give your answers in this format. (Eg is, is not)
(a)
∠r
= 180° - 76°
= 104° (Interior angles)
(b)
∠MKN
= ∠JKL
= 104° (Parallelogram)
∠JKP
= 180° - 90° - 20°
= 70° (Angles sum of triangle)
∠s
= 360° - 104° - 104° - 20° - 70°
= 62° (Angles at a point)
(c)
∠KPN
= 180° - 26° - 62°
= 92°
Since ∠KPN is not 90°, it does not add up to 180° with ∠JPK to form a straight line. So, JPN
is not a straight line because the sum of angles JPK and KPN
is not 180°.
Answer(s): (a) 104°; (b) 70°; (c) is not, is not