Question

Who is good at geometry that can help me?

Answer 1

Answer: d. 3

Explanation:

By the The intersecting chords theorem,

`x(x+3) = 2* 9`

`\implies x^2+3x=18`

`\implies x^2+3x-18=0`

`\implies x^2+6x-3x-18=0`

`\implies x(x+6)-3(x+6)=0`

`\implies (x-3)(x+6)=0`

`\text{ if }x-3=0\implies x = 3`

or
`\text{ if }x+6=0\implies x = -6` ( can not possible)

Hence, x = 3

⇒ Option d is correct.