Ai Tong School P5 SA1 2006 Math (Q39)

ABCD is a rectangle (not drawn to scale). AX = XD and AY = YB. Find the area of triangle CXY.


Solution

Area of rectangle ----- length x breadth
= 14 cm x 8 cm = 112 square cm

Area of Triangle CDX ----- ½ x base x height
= ½ x 14 cm x 4 cm = 28 square cm

Area of Triangle AXY ----- ½ x 7 cm x 4 cm = 14 square cm

Area of Triangle CBY ----- ½ x 7 cm x 8 cm = 28 square cm

Area of Triangle CXY -----
Area of rectangle – Area of Triangle CDX – Area of Triangle AXY – Area of Triangle BCY
= (112 – 28 – 14 – 28) square cm
= 42 square cm

Answer: Area of Triangle CXY is 42 square cm.