ANSWER

Step-by-step explanation
We want to find the value of x from the figure.
The line that touches the circle from outside the circle is called a tangent. When a tangent touches the radius of a circle, it makes a right angle with the radius.
This means that the triangle in the figure is a right-angled triangle:
Now, we can solve for x using the Pythagoras theorem:

where hyp = hypotenuse of the triangle
a, b = legs of the triangle
This means that:
![\begin{gathered} x^2=15^2+20^2 \\ x^2=225+400=625 \\ x=\sqrt[]{625} \\ x=25 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/u077mm7ugehw4tajtdmjfd2lz70meyggg6.png)
That is the value of x.