a) MB = AB - AM = 6 - x
Aria MBCG = MB * BC = ( 6 - x ) * 5 = 30 - 5 * x
b) MBCG ESTE DREPTUNGHI ==> MB = GC = 6 - x si BC = MG = 5
DG = DC - GC = 10 - ( 6 - x ) = 10 - 6 + x = 4 + x
AMGD Trapez !
=> Aria AMGD = (baza mica+baza mare)* inaltimea /2 (((( asta ii aria generala a trapezului si acum inlocuim ))))
Aria AMGD = ( AM + DG ) * MG / 2
Aria AMGD = { x + ( 4 + x ) } * 5 /
Aria AMGD = ( 2 * x + 4) * 5 / 2
Aria AMGD = ( 10 * x + 20 ) / 2
Aria AMGD = 5 * x + 10
Aria AMGD = 5 * ( x + 2 )
c)Aria AMGD = Aria MBCG
5 * ( x + 2 ) = 30 - 5 * x ( Ariile celor 2 le-am calculat pe punctul a) si b) )
5 * x + 10 = 30 - 5* x
10 * x = 20
x = 2