The sum of the inner angles of a polygon with n sides is 
Since your polygon has 6 sides, the sum of its inner angles has to be

On the other hand, the sum of its inner angles is

And it has to be 720, so we have

Answer: 3(x)≥15 →x≥5
Step-by-step explanation:
Set it up with x as the number of days. Then multiply that by 3, so that you get 3(x). This will show that for an x amount of days, you ran 3 miles. then set it to MORE THAN or EQUAL TO 15. Then divide both sides by 3, and you get the above answer.
The answer to this problem is X<3
Answer: 1.3125 gallons
Step-by-step explanation: The machine pumps 2.1 gallons of water every 1.6 minutes. 1.6 minutes is 1.6x more than 1 minute. So, we have to divide 1.6 by 1.6. Next, we have to divide 2.1 by 1.6. We can make this a bit easier by multiplying both of them by 10 to get 21/16 which is 1.3125.
<span>4y-9=15
Add 9 to both sides.
4y = 24
Divide both sides by 4.
y = 6
The value of y is 6.</span>