Question

ABCD un dreptunghi cu aria de 144 cm ^2. Aflati perimetrul dreptunghiului daca :
a) AB=4BC 
b) AB=9BC 

Answer 1

AB x BC= 144 cm
a) 4BC x BC= 144 cm
BC²= 144 cm : 4
BC= √36 cm
BC= 6 cm
AB= 4BC
AB= 6 x 4  cm= 24 cm
PABCD= 2(AB+BC)
P= 2( 24+6)
P= 30 x 2
P= 60cm
b)AB =9 BC
AB x BC =144 CM
9 BC × BC =144 cm
BC² = 144 : 9
BC = √ 16 cm
BC= 4 cm

Answer 2

BC=a
AB=4BC=4a
aria = a*4a=4a²=144
a²=36
a=6
AB=4*6=24
perimetrul = 2(6+24)=60 cm

BC=a
AB=9BC=9a
aria = a*9a=9a²=144
a²=16
a=4
AB=9*4=36
perimetrul = 2(4+36)=80 cm