Question

Would appreciate help with this question I'm confused about @_@

Answer 1

I thought the answer was 4 but it wasn't

Answer 2

I am not familiar with this technique, but I did manage to find a YouTube video explaining how to solve this kind of problem

https://www.youtube.com/watch?v=fUszhfJynd4

Answer 3

I don't really understand the geometric justification, but it this seems to be the basic concept: If you have two chords that intersect within a circle, the lengths of the segments of one chord multiplied together will be equal to the lengths of the segments of the other chord multiplied together.

In this problem, one chord has segments (7x+2) and (18); the other chord has segments (6x+3) and (20). Based on what I've just learned, we can represent the relationship in the following equation:

(7x + 2) * 18 = (6x + 3) * 20

Using that, you should be able to do some algebra and solve for x. What do you think?

Answer 4

Right, I did that and I came to the conclusion that x = 4 but if I plugged it back in it wouldn't work.

Answer 5

Interesting. Let me try working through it to check that real quick....

(7x + 2) * 18 = (6x + 3) * 20
126x + 36 = 120x + 60
6x = 24
x = 4.

Hm. Yup, I got the same answer with that method. How odd. Maybe I was mistaken about the method....?

Answer 6

Maybe add the segments together
(7x+2) + 18 = 20 + 6x + 3
x=3

Answer 7

@m4nt1c0r3 When you determined that 4 was not the correct answer, how did you get that information?

Answer 8

I plugged it back into the equation.

Answer 9

(7(4) + 2) * 18 = (6(4) + 3) * 20
30(18) = 27(20)
540 = 540

Answer 10

Ha? Are you sure? Not for me... maybe I'll do it again..

Answer 11

Yeah, I agree with snowflake, I think the numbers come out like we would expect them to, just like they wrote out

Answer 12

Oh you're right thanks!

Answer 13

Awesome. No problem, glad we could help!