Răspuns :
P=2(L+l)
L=l+1
2(l+1+l)=30
2(2l+1)=30
2l+1=30:2
2l=15-1
2l=14
l=14:2
l=7 cm are latimea
L=l+1=7+1=8 cm are lungimea
P=perimetru
L=l+1
2(l+1+l)=30
2(2l+1)=30
2l+1=30:2
2l=15-1
2l=14
l=14:2
l=7 cm are latimea
L=l+1=7+1=8 cm are lungimea
P=perimetru
notam dimensiunile a si a+1
P=2 (L+l)=2 ( a+a+1)
30=2( a+a+1) I:2
15=a+a+1
2 a+1=15
2 a=14
a=14/2=7
a+1=7+1=8 deci dimensiunile sunt 7 si 8
P=2 (L+l)=2 ( a+a+1)
30=2( a+a+1) I:2
15=a+a+1
2 a+1=15
2 a=14
a=14/2=7
a+1=7+1=8 deci dimensiunile sunt 7 si 8