tin chu so tan cung cua

a) \(7.2^{13}.2^{16}\)                                             b) \(21^{15}.27^5.49^8\)                                                  c)\(199^{20}.2003^{15}\)

toan quoc te nha

Question 1:
There are two parallel lines in the figure. What is the value of x? 

 Answer: x = 

Question 2:


ABC and RTS are similar triangles.
The value of x is 

Question 3:
If x<0 and 5x+8+|3x|=0 then x=

Question 4:
I am a multiple of 70 between 400 and 600. My tens digit is odd. Who am I?

Answer: 

Question 5:
How many triples of integers (a,b,c) are there such that 
 ? 
Answer:  triples.

Question 6:
Each of the 37 students in the grade 8 at a school has one dog or one cat or both a dog and a cat. Twenty students have a dog and 24 students have a cat. 
How many students have both a dog and a cat?
Answer:  students.

Question 7:
The sum of 2 positive integer numbers is greater than their product if the smaller number is 

Question 8:
How many different real numbers satisfy the following equation?
 
Answer: 

Question 9:
The area of trapezoid ABCD is 180   .The altitude is 8 cm,AD is 10 cm,and BC is 17 cm.
What is AB,in centimeters?

Answer:  cm.

Question 10:
There are 115 cars in a village of 26 families. Each family has either 4 or 5 cars. 
How many families have 4 cars? 
 Answer:  families.