Question

un trapez are aria egala cu 48 cm2 stiind ca inaltimea este de 3 cm afla lungimea liniei mijlocii a trapezului

Answer 1

$A= \frac{(B+b)*h}{2} =48 \\ h=3 \\ \\ lm= \frac{B+b}{2} \\ \\ lm*3=48 \\ \\ \boxed{lm=\frac{48}{3}= 16}$

Answer 2

linia mijlocie= $\frac{baza.mica+baza.mare}{2}$
48=b+B x 3/2
b+B=48:3
b+B/2=16
linia mijlocie=semisuma bazelor=16