(12 - 2) * 180 = 1,800/12 = 150
(8 - 2) * 180 = 1,080/8 = 135
B. 8 sides
277 good luck on whatever you need this for
Answer:
20,365.7 seconds
Step-by-step explanation:
First, we need to know how to convert yards to miles, as the question is in miles. We know that 1 mile is equivalent to 1760 yards. So we have:
1 mi = 1760 yards
If we multiply both sides by 81:
81 mi = 142,560 yards
And we know that the sprinter needs 8 second to run 56 yards:
8 s = 56 yards
If we divide both sides by 56 we get the time he needs for 1 yard:
8/56 s = 56/56 yards
1/7 s = 1 yard
So, takes him 1/7 seconds to run one yard. At this rate he runs 142,560 yards in:
(1/7) * 142,560 = 20,365.7
So, he needs 20,365.7 seconds to run 81 miles (142,560 yards)
Answer: The perimeter is 30ft.
Step-by-step explanation:
Let's define:
L = length of the longer side.
S = length of the shorter side.
P = perimeter
we know that for a common rectangle:
P = 2*S + 2*L
We aso know that:
L = 2ft + (1/3)*P
S = (1/10)*P
L = S + 9ft.
So we have a system, let's find the perimeter only using this system (So i will ignore the equation for the perimeter of a rectangle)
First, we can replace the third equation in the first equation, now we have a system with only two equations:
S + 9ft = 2ft + (1/3)*P
S = P/10
Now we can replace the second equation in the first equation, and get:
P/10 + 9ft = 2ft + P/3
Now let's solve this for P.
9ft - 2 ft = P/3 - P/10
7ft = P( 1/3 - 1/10) = P*( 10/30 - 3/30) = P*(7/30)
(30/7)*7ft = P = 30ft.
The perimeter is 30ft.
