### Home > GC > Chapter 6 > Lesson 6.1.2 > Problem 6-14

6-14.

Which trigonometric ratio can you use to solve for *x*?

What do the tick marks on the sides of the triangle mean?

How can you use that knowledge to solve for *x*?

Because of the marks, the lengths of the sides are the same.

Since this is a Right Isosceles triangle, use the Pythagorean Theorem.

*x* ≈ 9.9

Use the Law of Cosines to solve for x.

*x* ≈ 9.54