Question

cho tam giac abc vuong can tai A. Lay diem D bat ky thuoc canh Bc. Tu B,C ve BI, CK vuong goc voi AD tai I,K.

a) CM goc ACK phu voi goc KAC, CM goc BAI= ACK

b) CM BI=AK

c) CM BI² + CK² ko doi khi D chay tren BC

GIUP MK NHA!!! Thanks <3

Answer 1

kho the cau hoi nay minh cung dang can hoi

Answer 2

hinh tu ve

a) vi tam giac ack vuong tai k suy ra goc ack phu voi goc a ( trong 1 tam giac 2 goc nhon phu nhau )

co goc A_{1 +} A₂ ( tam giac akc vuong tai k) nen suy ra goc A1 = goc akc

b) xet tam giac abi va tam giac cak co

goc bia = goc akc = 90 do

ab =ac (gt)

goc A1 bang goc ack (cmt) nen 2 tam giac bang nhau ( canh huyen - goc nhon) nen suy ra bi =ak ( 2 canh ...)

c) xet tam giac abi co goc i bang 90 do suy ra ab² =ac^2 +ib ²

ma ai= ck ( vi tam giac abi = tam giac cak) suy ra ab^ 2 = ck^2 va ab ko doi suy ra bi^ 2 + ck^2 ko doi khi d chay tren bc

DUOC CHUA HA CON NHO LOP PHO