252,232 views
17 votes
17 votes
MACD - AABE, find the value of x,C3x + 8B20A X-1E27DA. 12.51B14,28c16D 11

MACD - AABE, find the value of x,C3x + 8B20A X-1E27DA. 12.51B14,28c16D 11-example-1
User Niklas Fasching
by
2.0k points

1 Answer

20 votes
20 votes

Given that the triangle ACD and ABE are similar.


\Delta ACD\text{ \textasciitilde }\Delta ABE

Then their corresponding sides must be proportional;


(BE)/(CD)=(AE)/(AD)

Given;


\begin{gathered} BE=20 \\ CD=3x+8 \\ AE=x-1 \\ AD=x-1+27=x+26 \end{gathered}

substituting the given values;


\begin{gathered} (BE)/(CD)=(AE)/(AD) \\ (20)/(3x+8)=(x-1)/(x+26) \end{gathered}

cross multiply and solve;


\begin{gathered} 20(x+26)=(3x+8)(x-1) \\ 20x+520=3x^2-3x+8x-8 \\ 20x+520=3x^2+5x-8 \\ 3x^2+5x-8-(20x+520)=0 \\ 3x^2-15x-528=0 \end{gathered}

solving the quadratic equation, we have;


\begin{gathered} 3(x-16)(x+11)=0 \\ so; \\ x=16 \\ or \\ x=-11 \\ \text{ since x cannot be negative then;} \\ x=16 \end{gathered}

Therefore, the value of x is;


undefined

User David Beck
by
2.8k points