Question

na figura r//s//t. determine a medida do segmento AB

resposta x= 5/4

Answer 1

Paralelas cortadas por uma diagonal:

$\frac{AB}{DE} = \frac{BC}{EF} \\ \\ \frac{2x+1}{4}= \frac{5x-1}{6} \\ \\ 6(2x+1)=4(5x-1) \\ \\ 12x+6=20x-4 \\ \\ 20x-12x=6+4 \\ \\8x=10 \\ \\ x= \frac{10}{8} \\ \\ x= \frac{5}{4}$

AB= 2x+1 ==> AB= 2*5/4 ==> AB=2*5/4+1
AB=10/4+1 ==> AB= (10+4)/4= 14/4= 7/2
AB= $3 \frac{1}{2} = 3,5$