Please someone help me answer my question need help

Question

asked Jul 23, 2019 189k views

1 Answer

Ritesh Bhat · Answer 1 · 2019-07-27T15:16:13+0000

Look at the picture.

The triangle ADC and the triangle CDB are similar.

Therefore corresponding sides are all in the same proportion:

$(y)/(4)=(12)/(y)\ \ \ \ |cross\ multiply\\\\y^2=48\to y=√(48)\\\\y=√(16\cdot3)\\\\y=√(16)\cdot\sqrt3\\\\y=4\sqrt3$

Answer: 4√3