In Fig. 8.129, PQ++RS, ∠AEF =95°, ∠BHS =110° and ∠ABC =x°. Then the value of x is,
Given that,
PQ ‖ RS
∠AEF = 95o
∠BHS = 110o
∠ABC = xo
∠AEF = ∠AGH = 95o (Corresponding angles)
∠AGH + ∠HGB = 180o (Linear pair)
95o + ∠HGB = 180o
∠HGB = 85o
∠BHS + ∠BHG = 180o (Linear pair)
110o + ∠BHG = 180o
∠BHG = 70o
In BHG,
∠BHG + ∠HGB + ∠GBH = 180o
70o + 95o + ∠GBH = 180o
∠GBH = 25o
Thus,
∠ABC = ∠GBH = 25o