Question

Teorema de Tales 12/2X 21/3X+5
Me ajudem PF!!

Answer 1

$\frac{12}{2x} = \frac{21}{3x +5 } \\ \\ 12(3x + 5) = 21 \cdot2x \\ 36x + 60 = 42x \\ 36x - 42x = - 60 \\ - 6x = - 60 \: \color{red} { \cdot( - 1) } \\ 6x = 60 \\ x = \frac{60}{6} \\ \boxed{ \bf{x = 10} }$

Espero ter ajudado! :)