I would like some help with a two part question. Please and thank you.

Given the triangle ACE
BD // CE
So, the segments between the parallel lines will be proportional
AB = 4
BC = 6
AD = x+3
DE = 2x+1
so,
[tex]\begin{gathered} \frac{AB}{BC}=\frac{AD}{DE} \\ \\ \frac{4}{6}=\frac{x+3}{2x+1} \\ \\ 4\cdot(2x+1)=6\cdot(x+3) \\ 8x+4=6x+18 \\ 8x-6x=18-4 \\ 2x=14 \\ \\ x=\frac{14}{2}=7 \end{gathered}[/tex]So, the value of x = 7
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Given if CE = 30
We need to find the length of BD
So, using the similarity between the triangles ABD and ACE
So, the corresponding sides will be proportionals
So,
[tex]\frac{AB}{AC}=\frac{BD}{CE}[/tex]AB = 4
AC = 4+6 = 10
CE = 30
So,
[tex]\begin{gathered} \frac{4}{10}=\frac{BD}{30} \\ 10\cdot BD=4\cdot30 \\ 10\cdot BD=120 \\ \\ BD=\frac{120}{10}=12 \end{gathered}[/tex]So, the length of BD = 12