For context, there's a right triangle with top point L, bottom right point S, and bottom left point Y. YS is the leg on the bottom of the triangle, Yl is the hypotenuse, and Ls the other Leg

If YS=6.3 km and YL=15.4 km, find the length of LS. Round your answer to the nearest tenth if necessary.
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1 answer

To solve for the length of leg LS in the right triangle with vertices L, S, and Y, we can use the Pythagorean theorem. The Pythagorean theorem states that for a right triangle with legs \( a \) and \( b \), and hypotenuse \( c \):

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

In this case, we have:

  • \( YS = 6.3 \) km (one leg of the triangle)
  • \( YL = 15.4 \) km (the hypotenuse)
  • \( LS \) is the other leg we need to find.

Assigning the lengths to the variables:

  • Let \( a = YS = 6.3 \) km
  • Let \( c = YL = 15.4 \) km
  • Let \( b = LS \) (the unknown leg we want to find)

We will apply the Pythagorean theorem:

\[ YS^2 + LS^2 = YL^2 \]

Plugging in the known values:

\[ (6.3)^2 + LS^2 = (15.4)^2 \]

Calculating \( (6.3)^2 \) and \( (15.4)^2 \):

\[ 6.3^2 = 39.69 \] \[ 15.4^2 = 237.16 \]

Substituting these values into the equation:

\[ 39.69 + LS^2 = 237.16 \]

Now, subtract \( 39.69 \) from both sides to solve for \( LS^2 \):

\[ LS^2 = 237.16 - 39.69 \] \[ LS^2 = 197.47 \]

Next, we take the square root of both sides to find \( LS \):

\[ LS = \sqrt{197.47} \] \[ LS \approx 14.04 \]

Rounding to the nearest tenth gives:

\[ LS \approx 14.0 \text{ km} \]

Thus, the length of \( LS \) is approximately 14.0 km.