Question

1. Calcule o valor de x: ​

Answer 1

$\boxed{\begin{array}{l}\rm\triangle~ABC\sim CDE\\\\\rm\dfrac{x}{4}=\dfrac{12}{3}\\\\\rm 3x=48\\\rm x=\dfrac{48}{3}\\\\\rm x=16\end{array}}$

$\boxed{\begin{array}{l}\rm b)~\triangle ABC\sim\triangle~CDE\\\rm\dfrac{4}{6}=\dfrac{5}{x}\\\\\rm 4x=30\\\rm x=\dfrac{30\div2}{4\div2}\\\\\rm x=\dfrac{15}{2}\end{array}}$

$\boxed{\begin{array}{l}\rm c)~\triangle~ABC\sim\triangle ~ADE\\\rm\dfrac{10}{\diagdown\!\!\!\!\!\!18_3}=\dfrac{x}{\diagdown\!\!\!\!\!\!24_4}\\\\\rm\dfrac{10}{3}=\dfrac{x}{4}\\\\\rm 3x=40\\\rm x=\dfrac{40}{3}\end{array}}$