Answer:
OW = 8
Step-by-step explanation:
It states that WC is a tangent to the circle. The line OW is the radius of the circle that meets the tangent, the circle theorem rule is that the angle a tangent makes to a radius of a circle is 90°. So angle CWO is 90°. This makes triangle CWO a right angle triangle.
Now we can use Pythagoras theorem to find the value of OW.
In the theorem c is the longest side of a right angled triangle and a and b are the smaller sides:
c² = a² + b²
So we can rearrange the equation to find on of the smaller sides:
a² = c² - b²
OW² = 17² - 15²
OW² = 289 - 225
OW² = 64
OW = √64
So OW is 8.