Answer:
about 8 cm
Step-by-step explanation:
The formula for the area of a regular polygon is ...
A = 1/2Pa . . . . where P is the perimeter and "a" is the apothem, the distance from the center to a side
Filling in your numbers, we have ...
20 cm^2 = (1/2)P(5 cm)
Dividing by the coefficient of P, we find ...
2×(20 cm^2)/(5 cm) = P = 8 cm
The perimeter of the pentagon is about 8 cm.
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<em>Comment on the problem</em>
This calculation makes use of the area formula, as apparently intended. A regular pentagon with an apothem of about 5 cm will have an area of about 90.8 cm^2. The given geometry is impossible, as the pentagon is nearly 10 cm across. It cannot have a perimeter of only 8 cm.
1. The triangle is Isosceles and acute A (since there are two equal sides and the angles are less than 90)
2. Right triangle E (since there is a right angle)
3. The triangle is obtuse scalene T (since there are no equal sides and one angle is greater than 90)
4. Right isosceles O
5. Acute equilateral N
6. Obtuse scalene T<span />
The answer is D. Most of the other answers are way to high to make sense
Answer:
Step-by-step explanation:
Let Alex's age = x
Mark's age = y
Luke's age = a
x + y + z = 12
The possible combinations for their age are
1. 6, 3, 3
2. 3, 3, 6
3. 4,4, 4
4, 2, 2, 8
5. 8, 2, 2
6. 2, 8, 2
7. 9, 2, 1
Etc the age can keep going as long as you can find any three numbers and add them to give you 12
Since we're given y, we can substitute y into the first euqation...
-2x+3(3x+4)=19
-2x+9x+12=19
7x=7
x=1
hope this helps :D brainliest pls
