Question

I don't know how to solve this

Answer 1

Hello,

Explanation:

using Thalès 's théorem :

`(x)/(x+10) =(4)/(10) \\\\10x=4x+40 \ (cross\ products)\\\\6x=40\\\\x=(20)/(3) \ (simplified\ by\ 2)`

x≈6.7 (i don't know what d.p. means , perhaps 1 decimal after the point)