Question

find the value of x.
x = ?

Explanation:

Step1: Use similar - triangle property

Since $\triangle BDE\sim\triangle BAC$, we have $\frac{BD}{BA}=\frac{BE}{BC}$. So, $\frac{x + 5}{2x+(x + 5)}=\frac{4}{4 + 3}$.

Step2: Cross - multiply

$7(x + 5)=4(3x + 5)$.

Step3: Expand and solve

$7x+35 = 12x+20$, $5x = 15$, $x = 3$.

Answer:

$3$