JAMB - Mathematics (2009 - No. 24)
In the figure above , TS//XY and XY = TY, ∠STZ = 34°, ∠TXY = 47°, find the angle marked n?
47o
52o
56o
99o
Giải thích
In Δ TYX
XY = TY ∴y =47° base ∠s of ISCΔ
But y+x+34+47 = 180 interior
opposite ∠s are supplementary
47 + x + 34 + 47 = 180
x + 128= 180
x = 180- 128
x = 52°