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1. This is Lan. She lives in Bao Loc city
2. She is tall and thin
3. She has black hair
4. She wears blue dress
5. She's beautiful
1 This is Lan. She lives in Bao Loc city
She is tall and thin
She has black hair
She wears blue dress
She is beautiful
![](https://rs.olm.vn/images/avt/0.png?1311)
![](https://rs.olm.vn/images/avt/0.png?1311)
kẻ bz song song với cy và tia đối Ax'với Ax , cy' với cy
vì Ax' là tia đối của Ax nên :
góc BAx'= 180độ - 150độ =30độ (vì là góc kề bù )
vậy góc BAx'=góc ABz=30độ suy ra Ax//Bz
Vậy Cy//Ax
![](https://rs.olm.vn/images/avt/0.png?1311)
tại sao lại hỏi hạng tử chính giữa nhỉ, do phép cộng có tính chất giao hoán, nên số nào cũng có thể đứng chính giữa.
![](https://rs.olm.vn/images/avt/0.png?1311)
3:
ΔABC vuông tại A có AH là đường cao
nên AB^2=BH*BC; AC^2=CH*CB
=>BH/CH=(AB/AC)^2=9/16
=>BH/9=CH/16
=>\(\dfrac{BH}{9}=\dfrac{CH}{16}=\dfrac{BH+CH}{9+16}=\dfrac{15}{25}=0.6\)
=>BH=5,4cm; CH=9,6cm
2:
a: ΔABC vuông tại A
=>BC^2=AB^2+AC^2
=>BC=căn 3^2+4^2=5(cm)
ΔABC vuông tại A có AH là đường cao
nên AH*BC=AB*AC; AB^2=BH*BC; AC^2=CH*CB
=>AH=3*4/5=2,4cm; BH=3^2/5=1,8cm; CH=4^2/5=3,2cm
b:
BC=BH+CH=25cm
ΔABC vuông tại A có AH là đường cao
nên AH^2=HB*HC; AB^2=BH*BC; AC^2=CH*CB
=>AH=căn 9*16=12cm; AB=căn 9*25=15cm; AC=căn 16*25=20cm
1. The film The Dark, which she watched last night, terrified her a lot.
2. Romeo and Juliet, whose parents hated each other, were lovers.
3. Do you remember the day when we first met?
4. Don’t use this product, which is not suitable to your hair.
5. This is a story of a man whose wife suddenly loses her memory.
6. Charlie Chaplin, whose films amused millions of people in the world, died in 1977.
7. Please post these letters, which I wrote this morning.
8. The building whose tower can be seen from afar is the church.
9. Mary and Margaret, whom you met yesterday, are twins.
10. I’ll introduce you to the man whose support is necessary for your project.
11. We enjoy traveling to Dalat, where there are a lot of places of interest.
12. Mary, whose sister I know, has won an Oscar.
13. Many rivers around the world are polluted, which caused serious diseases to people using the river water.
14. Shakespeare, who is the world’s greatest dramatist and poet, was born at Stratford on Avon, small town in England.
15. His girlfriend, whom he trusted absolutely, turned out to be an enemy spy.