Perimeter of a Triangle - Pre-Algebra
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What is the perimeter of a right triangle with hypotenuse 
and a leg of length 
?
What is the perimeter of a right triangle with hypotenuse
Using the Pythagorean Theorem, the length of the second leg can be determined.
We are given the length of the hypotenuse and one leg.
The perimeter of the triangle is the sum of the lengths of the sides.
Using the Pythagorean Theorem, the length of the second leg can be determined.
We are given the length of the hypotenuse and one leg.
The perimeter of the triangle is the sum of the lengths of the sides.
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Find the perimeter of the triangle above.
Note: Figure not drawn to scale.
Find the perimeter of the triangle above.
Note: Figure not drawn to scale.
The perimeter of a shape is the length around the shape. In order to find the perimeter of a triangle, add the lengths of the sides: 
.
Because the lengths are in inches, the answer must be in inches as well.
The perimeter of a shape is the length around the shape. In order to find the perimeter of a triangle, add the lengths of the sides:
Because the lengths are in inches, the answer must be in inches as well.
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Solve for the perimeter of the triangle.
Tom's, Bob's, and Fred's houses are in a triangle.
Tom's house is 
away from Bob's house. Fred's house is 
away from Bob's house. Fred's house is 
away from Tom's house.
What is the perimeter of the triangle between their houses?
Solve for the perimeter of the triangle.
Tom's, Bob's, and Fred's houses are in a triangle.
Tom's house is
What is the perimeter of the triangle between their houses?
The correct answer to the question is 
.
The formula for finding the perimeter of a triangle is to find the sum of the length of the 
sides.
The lengths of the three sides of this triangle are 
, 
, and 
. If you add these 
sides, the sum is a perimeter of 
.
The correct answer to the question is
The formula for finding the perimeter of a triangle is to find the sum of the length of the
The lengths of the three sides of this triangle are
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A right triangle has two short sides with lengths 5 and 12. What is the perimeter of the triangle?
A right triangle has two short sides with lengths 5 and 12. What is the perimeter of the triangle?
To begin, first find the length of the third side of the triangle. We are given that the two short sides of the triangle have lengths of 5 and 12. Use the Pythagorean Theorem to find the length of the third side:
,
where 
and 
represent the two shorter sides of the triangle, and 
is the hypotenuse:
Now that we have the lengths of all three sides, add them together to find the perimeter:
The perimeter of the triangle is 30.
To begin, first find the length of the third side of the triangle. We are given that the two short sides of the triangle have lengths of 5 and 12. Use the Pythagorean Theorem to find the length of the third side:
where
Now that we have the lengths of all three sides, add them together to find the perimeter:
The perimeter of the triangle is 30.
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What is the area of a triangle with a base of 
units and a height of 
units?
What is the area of a triangle with a base of
The equation for the area of a tirangle is 
The base in this equation is 
and the height is 
which can be plugged into the formula as:
Finally, we multiply to get:
The equation for the area of a tirangle is
The base in this equation is
Finally, we multiply to get:
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An equilateral triangle has one side with length 
. What is the perimeter of the triangle?
An equilateral triangle has one side with length
The key to solving this problem is remembering what an equilateral triangle is. In case you forgot, a quick word breakdown will help. It's easy to see that the first part of the word, "equi" looks an awful lot like equal. The second part, "lateral", is a little trickier, but we only need to remember that lateral means "side". In football, a lateral pass is when the player with the ball tosses it to a player on either side. Putting the two parts together, we see that equilateral just means equal sides. Therefore an equilateral triangle is a triangle where all three sides have equal length. That means that if one side of our equilateral triangle has length of 
, the other two sides are also each 
long.
We must also remember that the perimeter of a shape is just the distance around the outside of it. For our triangle, that means 
for the first side, 
for the second side, and 
for the third side. That means our perimeter is simply 
.
The key to solving this problem is remembering what an equilateral triangle is. In case you forgot, a quick word breakdown will help. It's easy to see that the first part of the word, "equi" looks an awful lot like equal. The second part, "lateral", is a little trickier, but we only need to remember that lateral means "side". In football, a lateral pass is when the player with the ball tosses it to a player on either side. Putting the two parts together, we see that equilateral just means equal sides. Therefore an equilateral triangle is a triangle where all three sides have equal length. That means that if one side of our equilateral triangle has length of
We must also remember that the perimeter of a shape is just the distance around the outside of it. For our triangle, that means
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One side of an equilateral triangle is 
. What is the triangle's perimeter?
One side of an equilateral triangle is
Equilateral triangles have 
sides of equal length. Therefore, by knowing the length of one side, we can calculate the perimeter by multiplying that length by 
.
Equilateral triangles have
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In equilateral triangle 
, 
.
What is the perimeter of triangle 
?
In equilateral triangle
What is the perimeter of triangle
Because the triangle is equilateral, all sidelengths are equal. Thus, if one is 8 they all must be 8, so 
Because the triangle is equilateral, all sidelengths are equal. Thus, if one is 8 they all must be 8, so
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For an isosceles triangle, if two of the sides are 3 and 6, which of the following is a possible perimeter?
For an isosceles triangle, if two of the sides are 3 and 6, which of the following is a possible perimeter?
In an isosceles triangle, two of the three sides are equal to each other. The possible side lengths of the isosceles are 
or 
.
The perimeter is the sum of the three sides.
The only possible perimeters given the two side lengths are either 
or 
.
The correct answer is: 
In an isosceles triangle, two of the three sides are equal to each other. The possible side lengths of the isosceles are
The perimeter is the sum of the three sides.
The only possible perimeters given the two side lengths are either
The correct answer is:
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What is the perimeter of an equilateral triangle with a length of 5?
What is the perimeter of an equilateral triangle with a length of 5?
There are three equal sides in an equilateral triangle.
Substitute the side length.
There are three equal sides in an equilateral triangle.
Substitute the side length.
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If the area of an equilateral triangle is 10, and the height is 10, what must be the perimeter of the triangle?
If the area of an equilateral triangle is 10, and the height is 10, what must be the perimeter of the triangle?
Write area formula for a triangle.
Substitute the area and the height to find the length of the base.
The base, or the length one side of the triangle, is two.
An equilateral triangle has three equal sides. Multiply the base by three to find the perimeter.
The answer is: 
Write area formula for a triangle.
Substitute the area and the height to find the length of the base.
The base, or the length one side of the triangle, is two.
An equilateral triangle has three equal sides. Multiply the base by three to find the perimeter.
The answer is:
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What is the perimeter of an equilateral triangle with a side of 
?
What is the perimeter of an equilateral triangle with a side of
Write the formula to find the perimeter of an equilateral triangle. All three sides are equal.
Substitute the side length.
Write the formula to find the perimeter of an equilateral triangle. All three sides are equal.
Substitute the side length.
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What is the perimeter of an isosceles triangle with a base length of 
?
What is the perimeter of an isosceles triangle with a base length of
For an isosceles triangle, two of the side legs are equal. It is necessary to know two of the three sides in order to sum the lengths. The problem only gave us the length of the base.
There is not enough information to solve this question since the length of the other leg is unknown.
For an isosceles triangle, two of the side legs are equal. It is necessary to know two of the three sides in order to sum the lengths. The problem only gave us the length of the base.
There is not enough information to solve this question since the length of the other leg is unknown.
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Find the perimeter of an isosceles triangle with a base of 4 inches and side length of 10 inches.
Find the perimeter of an isosceles triangle with a base of 4 inches and side length of 10 inches.
An isosceles triangle has two sides that have the same length. If the base is 4 and one of the sides is 10, then the other side is also 10.
An isosceles triangle has two sides that have the same length. If the base is 4 and one of the sides is 10, then the other side is also 10.
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An isosceles triangle measures 
inches along its two equal sides, and 
inches along its third side. What is the perimeter of the triangle?
An isosceles triangle measures
To find the perimeter of any object, simply add the length of each side together. This triangle has sides of 4, 4, and 7, so the answer is:
inches
To find the perimeter of any object, simply add the length of each side together. This triangle has sides of 4, 4, and 7, so the answer is:
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An equilateral triangle measures 
inches along its side. What is the area of the triangle?
An equilateral triangle measures
To find the perimeter of any object, simply add the length of each side together. The best answer is:
square inches
To find the perimeter of any object, simply add the length of each side together. The best answer is:
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Find the perimeter of an equilateral triangle with a side of length 14 inches.
Find the perimeter of an equilateral triangle with a side of length 14 inches.
The formula for the perimeter of a triangle is
where a, b, and c are the lengths of each side.
We know that an equillateral triangle has 3 equal sides. Therefore,
Therefore, the perimeter of an equillateral triangle with a side of length 14 inches is 42 inches.
The formula for the perimeter of a triangle is
where a, b, and c are the lengths of each side.
We know that an equillateral triangle has 3 equal sides. Therefore,
Therefore, the perimeter of an equillateral triangle with a side of length 14 inches is 42 inches.
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A man is planting a flower bed in the shape of a triangle. It measures three feet along one edge, four feet along another, and five feet along its final edge. What is the perimeter of the triangle?
A man is planting a flower bed in the shape of a triangle. It measures three feet along one edge, four feet along another, and five feet along its final edge. What is the perimeter of the triangle?
To find the perimeter of any object, simply add the length of each side together. The best answer is:
square feet
To find the perimeter of any object, simply add the length of each side together. The best answer is:
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An isosceles triangle measures eight inches along its two equal sides, and ten inches along its third side. What is the area of the triangle?
An isosceles triangle measures eight inches along its two equal sides, and ten inches along its third side. What is the area of the triangle?
To find the perimeter of any object, simply add the length of each side together. The best answer is:
square inches
To find the perimeter of any object, simply add the length of each side together. The best answer is:
Compare your answer with the correct one above
An isosceles triangle measures 
inches along its two equal sides, and 
inches along its third side. What is the area of the triangle?
An isosceles triangle measures
To find the perimeter of any object, simply add the length of each side together. The best answer is:
inches
To find the perimeter of any object, simply add the length of each side together. The best answer is:
Compare your answer with the correct one above