Triangle ABC is a right triangle.
What is the length of AC?
20
21
40
58

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. how many hours after the truck's departure will the two meet?

1) prove that 731^3−631^3 is divisible by 100 2) prove that 99^3−74^3 is divisible by 25