# What is the measurement of side a?

### 12 Answers

- RRLv 72 months agoFavorite Answer
The Pythagorean theorem, states that the square of the length of the hypotenuse is equal to the sum of squares of the lengths of other two sides of the right-angled triangle.

a^2 + 9^2 = 12^2

a^2 = 12^2 - 9^2

a^2 = 144 - 81

a^2 = 63

a = 7.94

- Jim MoorLv 72 months ago
That "appears" to be a Right Angle, but that is not specified. What if it was 91 degrees???

So from the info given YOU CANNOT BE SURE OF AN ANSWER.

IF they told you it's 90 degrees (a Right Triangle), then use Pythagoras.

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- ComoLv 72 months ago
a² = 12² - 9²

a² = (12 - 9) (12 + 9)

a² = 3 x 21

a = √3 x √21

a = √63

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- Iggy RockoLv 72 months ago
Use the Pythagorean Theorem.

a^2 + 9^2 = 12^2

a^2 + 81 =144

a^2 = 63

a = √63

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- DavidLv 72 months ago
Using Pythagoras' theorem side 'a' is 3 times square root of 7 or about 7.94

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- PopeLv 72 months ago
You have given the lengths of two sides of a triangle, but have given no angles. No, there is no right angle in the given conditions. The best we can do is this inequality.

12 - 9 < a < 12 + 9

3 < a < 21

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- Govind 3iLv 42 months ago
Hypotenuse is 12

==> 12^2 = 9^2 + a^2

==> 144 = 81 + a^2

==> 144 - 81 = a^2

==> 63 = a^2

==> a = 8( approx)

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Thank you!