Question

  Làm giúp mik bài3,4 vs ạ

Answer 1

3.

a.

Do \(\Delta ABC=\Delta HIK\) nên \(AC=HK\)

Mà \(HK=7cm\) suy ra \(AC=7\left(cm\right)\)

b.

Chu vi tam giác ABC là:

\(AB+BC+AC=7+8+7=22\left(cm\right)\)

Do \(\Delta ABC=\Delta HIK\) nên chu vi tam giác HIK bằng chu vi tam giác ABC

Suy ra chu vi tam giác HIK là 22 (cm)

Answer 2

4.

a.

Do \(\Delta ABC=\Delta DMN\) nên \(\left\{{}\begin{matrix}\widehat{A}=\widehat{D}\\\widehat{B}=\widehat{M}\\\widehat{C}=\widehat{N}\end{matrix}\right.\)

Mà \(\widehat{M}=60^0\) suy ra \(\widehat{B}=60^0\)

Theo tính chất tổng 3 góc trong tam giác ABC:

\(\widehat{A}+\widehat{B}+\widehat{C}=180^0\)

\(50^0+60^0+\widehat{C}=180^0\)

\(\widehat{C}=180^0-50^0-60^0=70^0\)

b,

Do \(\widehat{A}=\widehat{D}\) mà \(\widehat{A}=50^0\) nên \(\widehat{D}=50^0\)

Do \(\widehat{C}=\widehat{N}\) mà \(\widehat{C}=70^0\) nên \(\widehat{N}=70^0\)