Answer:
Area = 50 cm²
Explanation:
Area of a trapezium ABDE = ½(a + b)h
where,
a = BD = 2.5 cm
b = AE = 7.5 cm
h = DE = ?
We need to find DE ti be able to calculate the area.
DE = CE - CD
DE = CE - 5
Since ∆ACE is similar to ∆BCD, therefore:
AE/BD = CE/CD
Plug in the values
7.5/2.5 = CE/5
Cross multiply
CE*2.5 = 7.5*5
CE*2.5 = 37.5
Divide both side any 2.5
CE = 37.5/2.5
CE = 15
Thus, DE = CE - 5 = 15 - 5
DE = 10
✅Area of trapezium = ½(BD + AE)DE
= ½(2.5 + 7.5)*10
= ½(10)10
= 50 cm²