Tự vẽ hình

a,Có \(\widehat{cAe}+\widehat{cAd}=180^{o^{ }}\)(Vì kề bù)

Vì Ad là p/g \(\widehat{cAe}\Rightarrow A_1=A_2=\frac{\widehat{cAe}}{2}=\frac{120^o}{2}=60^o\)

b,Ta có:\(A_1+bAd=180^o\)(vì kề bù)

\(\Rightarrow\widehat{bAd}=120^o\)

\(\Rightarrow bAd>bAc\left(120^o>60^o\right)\)

Mà \(\widehat{bAd}=2.\widehat{bAc}\)

=>Ac là p/g \(\widehat{bAd}\)

c, có \(\widehat{cAe}+A_4=180^o\)(vì kề bù)

\(\Rightarrow A_4=60^o\)

Có:\(\widehat{bAg}+A_4=180^o\)

\(\Rightarrow\widehat{bAg}=120^o\)

Vì Ah là p/g\(\widehat{bAg}\Rightarrow A_5=\widehat{bAg}\div2=60^o\)

TA có:\(\widehat{A_1}+A_4+A_5=60^o+60^o+60^o=180^o\)

\(\Rightarrow\widehat{dAh}=180^o\)

=>2 tia Ad và Ah đối nhau

My house in the future will be a candy house. It is a big house with syrup and fruit juice covering my house. In front of the house there will be a robot made of cakes, and welcome me very intimately when I return home. The house is decorated with 2 big candy trees. On top of the house there are chimneys and my house is surrounded by big trees. In my house there are 4 rooms: 1 living room, 2 bedrooms and a kitchen. My robots will do all the housework to help me. In the living room, there will be a table and many sofas. It will have a hi-tech TV, I can watch many different programmes. In the kitchen, there will be a stove, a fridge, a microwave. In each bedroom, there will be a king-size bed, an air-conditioner, some pillows, some blankets. I love my future house and I wish it will come true someday.

bought

didn't eat

Put the verbs in the correct form 

1.Nam(buy)...bought.....a new dress 5 days ago 

2.He(not eat)..didn't eat.........fish last night 

3.If he (wash)...washes......my car,I will give him 10 dollars

4.You(see)....saw.....a good movie yet?

\(C=\frac{2}{1.4}+\frac{2}{4.7}+\frac{2}{7.10}+...+\frac{2}{31.34}\)

\(C=\frac{2}{3}.\left(\frac{3}{1.4}+\frac{3}{4.7}+\frac{3}{7.10}+...+\frac{3}{31.34}\right)\)

\(C=\frac{2}{3}.\left(\frac{1}{1}-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+...+\frac{1}{31}-\frac{1}{34}\right)\)

\(C=\frac{2}{3}.\left(\frac{1}{1}-\frac{1}{34}\right)\)

\(C=\frac{2}{3}.\frac{33}{34}\)

\(C=\frac{11}{17}\)

\(C=\frac{2}{1.4}+\frac{2}{4.7}+\frac{2}{7.10}+...+\frac{2}{31.34}\)

\(=\frac{2}{3}\left(\frac{1}{1.4}+\frac{1}{4.7}+\frac{1}{7.10}+...+\frac{1}{31.34}\right)\)

\(=\frac{2}{3}\left(1-\frac{1}{4}+\frac{1}{4}-\frac{1}{7}+\frac{1}{7}-\frac{1}{10}+...+\frac{1}{31}-\frac{1}{34}\right)\)

\(=\frac{2}{3}\left(1-\frac{1}{34}\right)=\frac{2}{3}.\frac{33}{34}=\frac{11}{17}\)