Question

If triangle ABC is similar to triangle PQR ar(ABC)/ar(PQR)=9/4and PQ =8cm then find the length of AB

Answer 1

ar(ABC)/ar(PQR) = (3/2)^2
AB/PQ=3/2
AB/8=3/2
AB/4=3
AB=12cm (Ans)

Answer 2

we know that if two triangles are similar then,
ar of triangle ABC/ar of triangle PQR=ratio of side square then
9/4=ABsquare/64
9=AB square/16
AB square=144
Hence, AB=12.