Mot thua ruong hinh tam giac co day la 25m. Keo dai day them 5m thi dien tich tang them 50m2. Tinh dien tich manh dat khi chua mo rong. ( can ve hinh)
Mot mieng dat hinh thang co dien tich 864m vuong day lon hon day be 12m. Nguoi ta mo rong mieng dat bang cach tang day lon them 5m thi duoc mot mieng dat moi co dien tich bang 924m vuong. Tim do dai be va day lon cua manh dat hinh thang luc chua mo rong
CHO HÌNH VUÔNG ABCD NẾU MO RONG VE BEN TRAI 4M VA MO RONG VE PHIA DUOI 4M THI DIEN TICH SE TANG THEM 160M2 .TINH DIEN TICH HINH VUONG ABCD
mot san kho hinh vuong duoc mo rong ve phia ben phai 3m,phia duoi them 10m nen tro thanh hing chu nhat co chu vi bang 106m.Tinh dien tich san kho ban dau ?
Mot manh dat hinh chu nhat co chieu rong bang 2/3 chieu dai. Neu chieu dai giam di 5m va chieu rong tang them 5m thi dien tich tang 65m2. Tinh dien tich manh dat do.
1 manh dat hinh binh hanh co day dai 24m chieu cao bang 2/3 do dai chieu dai nguoi ta mo rong them ve hai phia de duoc manh dat hinh chu nhat co chieu dai gap doi chieu rong tinh xem dien tich phan mo ronh them bao nhieu m vuong
mot manh dat hinh tam giac co do dai day la 40 m chieu cao co do dai bang 2/5 day
tinh dien tich cua manh dat do
nguoi ta mo rong day manh dat dai them mot doan nua thi dien tich manh dat tang them 40 m2 tinh do dai day duoc mo rong
tinh ti so phan tram dien tich dat tang them va dien tich dat truoc khi chua mo rong
mot mieng dat hinh thang co dien tich 256,2 m,day nho 18m,day lon 30,8m.nguoi ta mo rong hai phia ben phai va ben trai de mieng dat tro thanh hinh chu nhat thi dien tich tang them bao nhieu
mieng dat hinh chu nhat co chieu dai gap 3 lan chieu rong.Nguoi ta mo ve 3 phia mot phia theo chieu dai va hai phia theo chieu rong thi dien tich tang them 123m2 . Tinh dien tich mieng dat sau khi mo rong , biet rang mo rong moi phia them 3m