Question

In the diagram at the right, the endpoints of the chord are thepoints where the line x = 5 intersects the circle x2 + y2 = 81.What is the length of the chord?

Answer 1

The length of the Chord is 15

SOLUTION:

Solve for y when x=5

`\begin{gathered} x^2+y^2=81 \\ y=\sqrt[]{81-x^2} \\ y=\sqrt[]{81-25} \\ y=7.5 \end{gathered}`

Since the value of y is 7.5 we multiply it by 2, to get the length

therefore, the length is 15