An illustration shows a larger triangle upper N upper T upper E and a smaller triangle upper K upper L upper A, with labeled sides. On the first triangle, side upper E upper N is the base labeled as 63, side upper T upper E is on the right labeled as 99, and side upper N upper T is on the left and is not labeled. On the second triangle, side upper A upper K is the base that is labeled as 7, side upper L upper A is on the right labeled as x, and side upper K upper L is on the left and is not labeled.

Triangle NTE is similar to triangle KLA. If TE = 99, EN = 63, and AK = 7, what is the length of LA?

1 answer

Since triangles \( NTE \) and \( KLA \) are similar, the ratios of the corresponding sides are equal. We can set up the ratio using the given side lengths:

\[ \frac{EN}{AK} = \frac{TE}{LA} \]

The values we have are:

  • \( EN = 63 \)
  • \( AK = 7 \)
  • \( TE = 99 \)

Let \( LA \) be the unknown side length we need to find. Plugging in the known values, we have:

\[ \frac{63}{7} = \frac{99}{LA} \]

Now, we can simplify the left side:

\[ \frac{63}{7} = 9 \]

So the equation becomes:

\[ 9 = \frac{99}{LA} \]

Now, we can cross-multiply to solve for \( LA \):

\[ 9 \cdot LA = 99 \]

Dividing both sides by 9 gives:

\[ LA = \frac{99}{9} = 11 \]

Thus, the length of \( LA \) is \( \boxed{11} \).