If a right triangle has a leg that measures 8 inches and the hypotenuse is 12 inches, how long is the other leg? Round to the nearest tenth, if necessary. Show your work.(1 point) inches

1 answer

To find the length of the other leg of a right triangle when one leg and the hypotenuse are known, we can use the Pythagorean theorem. The theorem states that in a right triangle, the sum of the squares of the two legs equals the square of the hypotenuse. This can be expressed with the formula:

\[ a^2 + b^2 = c^2 \]

where:

  • \( a \) and \( b \) are the lengths of the legs,
  • \( c \) is the length of the hypotenuse.

In this case:

  • One leg \( a = 8 \) inches,
  • The hypotenuse \( c = 12 \) inches,
  • We need to find the other leg \( b \).

Substituting the known values into the Pythagorean theorem:

\[ 8^2 + b^2 = 12^2 \]

Calculating the squares:

\[ 64 + b^2 = 144 \]

Next, we isolate \( b^2 \):

\[ b^2 = 144 - 64 \]

\[ b^2 = 80 \]

Now, we take the square root of both sides to find \( b \):

\[ b = \sqrt{80} \]

We can simplify \( \sqrt{80} \):

\[ \sqrt{80} = \sqrt{16 \times 5} = \sqrt{16} \times \sqrt{5} = 4\sqrt{5} \]

Now, we will calculate \( 4\sqrt{5} \). Approximating \( \sqrt{5} \) (which is about 2.236):

\[ b \approx 4 \times 2.236 \approx 8.944 \]

Rounding to the nearest tenth, we find:

\[ b \approx 8.9 \]

Thus, the length of the other leg is approximately 8.9 inches.