We will assume A×B = B×A and show that A and B are necessarily the same.
Assume A×B = B×A. Let a ∈ A and b ∈ B. Then (a,b) ∈ A×B. Since A×B = B×A, we have (a,b) ∈ B×A. That is, a ∈ B and b ∈ A. Therefore, a ∈ A implies a ∈ B and b ∈ B implies b ∈ A. So A = B, as we had set out to do.
Answer:
2 hours
Step-by-step explanation:
Given the following :
Darryl :
Speed = 25mph
Jacob:
Traveled in opposite direction
Speed = 35mph
After Darryl had traveled for 4 hours, Distance between them was 170 miles
Distance traveled by Darryl :
Speed * time = (25 * 4) = 100 miles
Total distance = distance traveled by Darryl + distance traveled by Jacob
170 miles = 100 miles + distance traveled by jacob
Distance traveled by Jacob = 170 - 100
Distance traveled by Jacob = 70 miles
Time = distance / speed
Time traveled by Jacob = 70 miles / 35mph
Time traveled by Jacob = 2 hours
Answer:
10 weeks
Step-by-step explanation:
350 - 128.85 = 221.15
221.15/ 22.25= 9.9
So 10 weeks
You take -30 and divide by -6 and your answer is n=5
2nd and 3rd option looks correct. 1st option is not true and I am pretty sure 4th one is not true as well