How to find the perimeter of a pentagon - ISEE Upper Level Quantitative Reasoning
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Find the perimeter of a pentagon with a side of length 12in.
Find the perimeter of a pentagon with a side of length 12in.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 21in.
Find the perimeter of a pentagon with a side having a length of 21in.
Tap to reveal answer
A pentagon has 5 sides. To find the perimeter, we will use the following formula:

where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get


A pentagon has 5 sides. To find the perimeter, we will use the following formula:
where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 15cm.
Find the perimeter of a pentagon with a side having a length of 15cm.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 9in.
Find the perimeter of a pentagon with a side having a length of 9in.
Tap to reveal answer
A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get


A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get
← Didn't Know|Knew It →
A pentagon has a side of length 11in. Find the perimeter.
A pentagon has a side of length 11in. Find the perimeter.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side of length 12in.
Find the perimeter of a pentagon with a side of length 12in.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 21in.
Find the perimeter of a pentagon with a side having a length of 21in.
Tap to reveal answer
A pentagon has 5 sides. To find the perimeter, we will use the following formula:

where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get


A pentagon has 5 sides. To find the perimeter, we will use the following formula:
where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 15cm.
Find the perimeter of a pentagon with a side having a length of 15cm.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 9in.
Find the perimeter of a pentagon with a side having a length of 9in.
Tap to reveal answer
A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get


A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get
← Didn't Know|Knew It →
A pentagon has a side of length 11in. Find the perimeter.
A pentagon has a side of length 11in. Find the perimeter.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side of length 12in.
Find the perimeter of a pentagon with a side of length 12in.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 21in.
Find the perimeter of a pentagon with a side having a length of 21in.
Tap to reveal answer
A pentagon has 5 sides. To find the perimeter, we will use the following formula:

where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get


A pentagon has 5 sides. To find the perimeter, we will use the following formula:
where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 15cm.
Find the perimeter of a pentagon with a side having a length of 15cm.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 9in.
Find the perimeter of a pentagon with a side having a length of 9in.
Tap to reveal answer
A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get


A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get
← Didn't Know|Knew It →
A pentagon has a side of length 11in. Find the perimeter.
A pentagon has a side of length 11in. Find the perimeter.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side of length 12in.
Find the perimeter of a pentagon with a side of length 12in.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 12in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 21in.
Find the perimeter of a pentagon with a side having a length of 21in.
Tap to reveal answer
A pentagon has 5 sides. To find the perimeter, we will use the following formula:

where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get


A pentagon has 5 sides. To find the perimeter, we will use the following formula:
where a is the length of a side of the pentagon.
Now, we know the length of a side of the pentagon is 21in.
Knowing this, we will substitute into the formula. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 15cm.
Find the perimeter of a pentagon with a side having a length of 15cm.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon. Because a pentagon has 5 equal sides, we can use any side in the formula.
So, we know the length of one side of the pentagon is 15cm. So, we can substitute. We get
← Didn't Know|Knew It →
Find the perimeter of a pentagon with a side having a length of 9in.
Find the perimeter of a pentagon with a side having a length of 9in.
Tap to reveal answer
A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get


A pentagon has 5 equal sides. To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know a side of the pentagon has a length of 9in. So, we get
← Didn't Know|Knew It →
A pentagon has a side of length 11in. Find the perimeter.
A pentagon has a side of length 11in. Find the perimeter.
Tap to reveal answer
To find the perimeter of a pentagon, we will use the following formula:

where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get


To find the perimeter of a pentagon, we will use the following formula:
where a is the length of one side of the pentagon.
Now, we know the length of one side of the pentagon is 11in.
Knowing this, we can substitute into the formula. We get
← Didn't Know|Knew It →