Find the area of a trapezium whose parallel sides are 25 cm, 13 cm and the other sides are 15 cm each.
In ΔCEF
CE = 10 cm and EF = 6cm
Using pythagorous theorem:
CE2 = CF2 + EF2
CF2 = CE2 - EF2
CF2 = 152 - 62
CF2 = 225-36
CF2 = 189
CF = 17 cm
Area of trapezium = area of parallelogram AECD + area of area of triangle CEF
Area of trapezium =
Area of trapezium =
Area of trapezium = 221 + 102 = 323 cm2