1. A) Aria ABCD=30m × 40m=1200m patrati
B) casa+ piscina = 120+34=154 m patrati
C) aria gradina = 1200-154=1046 m patrati
La ex 2
L=4,2dm=0,4m (cred ca ii greseala, nu are cum.lungimea sa fie mai mica decat latimea dar noi facem calculele dupa datele acestea)
l=5,3m
P=2×(0,4+5,3)=11,4
Aria=0,4×5,3=2,12m patrati
l=6cm
P=420mm=42cm
Atunci
P=2xl+2×L rezulta 42=2×6+2×L
2xL=42-12 rezulta Lungimea=30:2=15 cm
Aria=l×L=6×15=90 cm patrati
L=12m=120dm
P=360dm
360=2×latime+2×120
latime=(360-240):2=120:2=60dm
Aria=120×60=7200dm patrati
L=2400cm=24m
Aria=144m patrati
144=latime×24
latimea=144:24=6m
P=2(24+6)=60m
