Someone please help with this question (1 Viewer)

[hmim]

The Answer is (C) but i have no idea how they got that

 

[jimmysmith560]

Would the following working help?

 

[hmim]

Would the following working help?

View attachment 36904

Hmmm, why did you times (x+10) and x?

 

[jimmysmith560]

Hmmm, why did you times (x+10) and x?

This follows the property where the square of the length of the tangent from an external point is equal to the product of the intercepts of the secant passing through this point. Consider the following figure:



Here, .

The same applies to your question, i.e. .

 

[hmim]

This follows the property where the square of the length of the tangent from an external point is equal to the product of the intercepts of the secant passing through this point. Consider the following figure:

View attachment 36906

Here, .

The same applies to your question, i.e. .

Ahhh right, thank you so much for your help !

 

[Trebla]

Technically circle geometry is not in the syllabus (it can also be proved by similar triangles)…