ΔABC is similar to ΔPQR. The area of ΔABC is 64 cm2, and the area of ΔPQR is 121 cm2. If QR = 15.4 cm, what is the length of BC ?
Answer & explanation
Correct answer: option 3
We have,
ΔABC is similar to ΔPQR
Area of ΔABC = 64 cm2
Area of ΔPQR = 121 cm2
QR = 15.4 cm
According to concept:
\(\frac{ 64}{ 121}\) = \(\frac{ BC^2}{ QR^2}\)
= \(\frac{ 8}{11}\)= \(\frac{ BC}{ 15.4}\)
=BC = \(\frac{ (15.4 × 8)}{ 11}\)
= BC = 11.2 cm