29.99-20%= 23.99
25.00-10%= 22.50 so, Mr.chang got the better deal ( but not by much.)
Answer:
If 2m is the radius, the diameter is 4 meters.
2*2=4
He traveled 2080 miles after 4 hours. He covered 3640 miles in 7 hours with a constant speed, so we can calculate the speed: 3640/7=520 miles/hour. After 4 hours, he traveled 520*4=2080 miles.
Answer:
1) Let's consider the first case with the number 0 the oppose is also 0 and we have that 0-0=0 so then applies
2) Now let's consider any real number a no matter positive or negative we will have that:

Or in the other case:

So then we can conclude that the expression is a general rule and is true
Step-by-step explanation:
For this case we can verify if the following expression is true or false:
The sum of x and it’s opposite is always zero?
If we want to proof this we need to show that for any number is true.
1) Let's consider the first case with the number 0 the oppose is also 0 and we have that 0-0=0 so then applies
2) Now let's consider any real number a no matter positive or negative we will have that:

Or in the other case:

So then we can conclude that the expression is a general rule and is true
Step-by-step explanation:
Average between these no.s =


approx