Question

Let ABC and DEF are two similar triangles and thier areas be 64 cm square and 121 cm square respectively. If EF= 15. 4 cm then BC= ?

Answer 1

here it is given that it is similar triangle. we know that ratio of two similar triangle is equal to the square of the ratio of their side

Answer 2

$121 \div 64 = (15.4)^{2} \div bc {}^{2}$
$\sqrt{121 \div 84} = 15.4 \div bc \\ 11 \div8 = 15.4 \div bc \\ 11bc = 15.4 \times 8 \\ 11bc = 1232 \\ bc = 1232 \div 11 \\ bc = 112cm$