Ho fumana pherimitha ea sekwere: foromo le mesebetsi

Khatisong ena, re tla hlahloba mokhoa oa ho bala perimeter ea lisekoere le ho sekaseka mehlala ea ho rarolla mathata.

Foromo ea potoloho

Ka bolelele ba lehlakore

Pherimitha (P) ea sekwere e lekana le kakaretso ea bolelele ba mahlakore a eona.

P = a + a + a + a

Kaha mahlakore ohle a sekwere a lekana, foromo e ka hlahisoa joalo ka sehlahisoa:

P = 4 ⋅ a

Ka bolelele ba diagonal

Pherimitha (P) ea lisekoere e lekana le sehlahisoa sa bolelele ba diagonal le nomoro 2√2:

P = d ⋅ 2√2

Foromo ena e latela karo-karolelano ea bolelele ba lehlakore (a) le diagonal (d) ea sekwere:

d = a√2.

Mehlala ea mesebetsi

Mosebetsi 1

Fumana pherimitha ea lisekoere haeba lehlakore la eona le 6 cm.

Qeto:

Re sebelisa foromo eo boleng ba lehlakore bo amehang ho eona:

P = 6 cm + 6 cm + 6 cm + 6 cm = 4 ⋅ 6 cm = 24 cm.

Mosebetsi 2

Fumana pherimithara ea sekwere seo diagonal e leng √2 sheba

1 Tharollo:

Ha re ela hloko boleng boo re bo tsebang, re sebelisa foromo ea bobeli:

P = √2 cm ⋅ 2√2 = 4cm.

2 Tharollo:

Hlalosa bolelele ba lehlakore ho latela diagonal:

a = d / √2 = √2 cm/√2 = 1cm.

Joale, re sebelisa foromo ea pele, re fumana:

P = 4 ⋅ 1 cm = 4 cm.