Question

in the given figure , If l (AB) = 20 cm, l (BC) = 15 cm and l (PQ) = 15 cm and l (QR) = 10 cm in the rectangle PQRS, what is the area of ​​the underlined area?

1️⃣ 200 sq.cm.
2️⃣ 150 sq.cm.
3️⃣ 100 sq.cm.
4️⃣ 120 sq.cm.

Answer 1

Answer:

Given :

Area of ∆ ABCArea of ∆QRP = 94

AB = 18 cm , BC = 15 cm So PR = ?

We know when two triangles are similar then " The areas of two similar triangles are proportional to the squares of their corresponding sides.

Area of ∆ ABCArea of ∆ QRP = AB2QR2 = BC2PR2 = AC2QP2

So , we take

Area of ∆ ABCArea of ∆ QRP = BC2PR2

Now substitute all given values and get

94 = 152PR2

Taking square root on both hand side , we get

32 = 15PR

PR = 10 cm

Answer 2

length × breadth = 15 ×10

=150

Option 2nd is correct