Question

please explain it fast​

Answer 1

Answer:

first use Pythagoras theorem and find out the sides then find out the areas of the 2 triangles and add them

Answer 2

Answer:

Area of a trapezium ABCD = 390 cm²

Step-by-step explanation:

We have to find the area of trapezium ABCD.

Area of a trapezium = (1/2) × Sum of parallel sides × Height.

In the above figure,

Area of a trapezium ABCD = (1/2) × (AD + BC) × AB

It is given that AB = 20 cm, BC = 24 cm, and BD = 25 cm

We need to find the length of AD.

In Δ DBA , ∠DAB = 90°

Using pythagoras theorem,

BD² = AB² + AD²

(25)² = (20)² + AD²

625 = 400 + AD²

AD² = 625 - 400 = 225

AD = √225

AD = 15 cm.

So, Area of a trapezium ABCD = (1/2) × (AD + BC) × AB

= (1/2) × (15 + 24) × 20

= (1/2) × 39 × 20 = 39 × 10

= 390 cm²

∴ Area of a trapezium ABCD = 390 cm²