How to find the length of the side of a right triangle - Geometry
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Find the length of the unknown side,
, of the right triangle below.

Find the length of the unknown side, , of the right triangle below.
We need to use the Pythagorean Theorem, which says that
.
Since we need to find the length of 'a', we can just solve for 'a'.


In our case, c = 12 and b = 9.
Thus,
.
We need to use the Pythagorean Theorem, which says that .
Since we need to find the length of 'a', we can just solve for 'a'.
In our case, c = 12 and b = 9.
Thus, .
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The hypotenuse of a right triangle is 26 in and one leg is 10 in. What is the sum of the two shortest sides?
The hypotenuse of a right triangle is 26 in and one leg is 10 in. What is the sum of the two shortest sides?
We use the Pythagorean Theorem so the problem to solve becomes
where
= unknown leg length
So
and 
The sum of the two legs becomes 
We use the Pythagorean Theorem so the problem to solve becomes where
= unknown leg length
So and
The sum of the two legs becomes
Compare your answer with the correct one above
Compare your answer with the correct one above
Find the missing leg of the right triangle when one of the legs is
and the hypotenuse is
.
Find the missing leg of the right triangle when one of the legs is and the hypotenuse is
.
In order to find the missing side of a right triangle you must use one of two things:
1. Pythagorean Theorem
2. Trigonometry.
Since we only know what the side lengths are we must use the Pythagorean Theorem.

a=4, b=x, and c=5




So the missing side length is 3
In order to find the missing side of a right triangle you must use one of two things:
1. Pythagorean Theorem
2. Trigonometry.
Since we only know what the side lengths are we must use the Pythagorean Theorem.
a=4, b=x, and c=5
So the missing side length is 3
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Given that the hypotenuse of a right triangle is
and one side is
, find the other side length.
Given that the hypotenuse of a right triangle is and one side is
, find the other side length.
To find the length of the missing side, you can either use the pythagorean theorm or realize this is a case of a special right triangle with sides
.
Thus, the other side length is
.
To find the length of the missing side, you can either use the pythagorean theorm or realize this is a case of a special right triangle with sides .
Thus, the other side length is .
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Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side length.

Find the length of the missing side length.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above
Find the length of the missing side.

Find the length of the missing side.

Recall the Pythagorean Theorem for a right triangle:

Since the missing side corresponds to side
, rewrite the Pythagorean Theorem and solve for
.


Now, plug in values of
and
into a calculator to find the length of side
. Round to
decimal places.

Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for
.
Now, plug in values of and
into a calculator to find the length of side
. Round to
decimal places.
Compare your answer with the correct one above

Given the right triangle above, find the value of
.
Given the right triangle above, find the value of .
To find the length of the side x, we must use the Pythagorean Theorem
.
However, this time since we are given the value of the hypotenuse, we will solve for side b rather than c.
So, when we plug the given values into the formula, the equation looks like

which can be simplified to
.
Next, solve for b and we get a final answer of
.
This particular example is a Pythagorean triple, or a right triangle with 3 whole number values, so it is a good one to remember.
To find the length of the side x, we must use the Pythagorean Theorem
.
However, this time since we are given the value of the hypotenuse, we will solve for side b rather than c.
So, when we plug the given values into the formula, the equation looks like
which can be simplified to
.
Next, solve for b and we get a final answer of
.
This particular example is a Pythagorean triple, or a right triangle with 3 whole number values, so it is a good one to remember.
Compare your answer with the correct one above

Given the right triangle above, find the length of the missing side.
Given the right triangle above, find the length of the missing side.
To find the length of the side x, we must use the Pythagorean Theorem
.
However, this time since we are given the value of the hypotenuse, we will solve for side b rather than c.
So, when we plug the given values into the formula, the equation looks like

which can be simplified to
.
Next, solve for b and we get a final answer of
.
This particular example is a Pythagorean triple, or a right triangle with 3 whole number values, so it is a good one to remember.
To find the length of the side x, we must use the Pythagorean Theorem
.
However, this time since we are given the value of the hypotenuse, we will solve for side b rather than c.
So, when we plug the given values into the formula, the equation looks like
which can be simplified to
.
Next, solve for b and we get a final answer of
.
This particular example is a Pythagorean triple, or a right triangle with 3 whole number values, so it is a good one to remember.
Compare your answer with the correct one above