Toi can gap mai nop 2 cau
Mot hinh chu nhat neu chieu dai tang 20 phan tram va chieu rong giam 15 phan tram thi dien tich tang 20 dm2 tinh dien tich hinh chu nhat ban dau.
Them 1 bai nhe
Mot hinh chu nhat neu chieu dai tang 20 phan tram va chieu rong giam 25 phan tram thi dien tich giam xuong 60m2 tinh dien tich hinh chu nhat ban dau
tinh dien tich hinh chu nhat biet neu tang chieu dai len 30 phan tram va giam chieu rong di 20 phan tram thi dien tich tang len 28m2
dien tich hinh chu nhat tang hay giam bao nhieu phan tram neu chieu dai tang len 20 phan tram va chieu rong giam di 20 phan tram?
tinh dien tich hinh chu nhat biet neu chieu dai tang 30 phan tram so do ban dau va chieu rong giam 20 phan tram so do ban dau thi dien tich tang 28 met vuong,
cau 1 : mot cua hang ban lai 20% so voi gia ban . Hoi cua hang lai bao nhieu phan tram so voi gia von
cau 2 : de dien tich mot hinh chu nhat tang len gap doi ma chieu rong chi tang them 25% thi chieu dai phai tang them bao nhieu phan tram
cau 3 : neu giam do dai canh cua mot hinh vuong di 10% thi dien tich cua hinh vuong do giam di bao nhieu phan tram
cau 4 : neu tang do dai canh cua mot hinh vuong them 10% thi dien tich cua hinh vuong do tang them bao nhieu phan tram
Tinh diet tich hinh chu nhat .biet rang neu chieu rong tang 20 phan tram .chieu dai giam 20 phan tram thi dien tich la 360m2
tang chieu dai mot hinh chu nha them 10 phan tram dong thoi giam chieu rong hinh chu nhat do di 10 phan tram thi dien tich hinh chu nhat do giam di bao nhieu phan tram
dien tich hinh chu nhat do giam
mot hinh chu nhat co chu vi 120 m. neu tang chieu rong cua hinh chu nhat do them 10% va giam chieu dai di 10%thi ta duoc 1 hinh vuong .hoi:
a, chieu rong sau khi tang bang bao nhieu phan tram chieu rong ban dau
chieu dai sau khi giam bang bao nhieu phan tram chieu dai ban dau
b, tinh dien tich hinh chu nhat do.
chieu dai hinh chu nhat tang len 20% thi chieu rong giam di bao nhieu phan tram de dien tich hinh chu nhat khong thay doi